Steps & Walking
Steps counted honestly — distance, energy and the stride underneath them.
20 calculators · steps, pace, gears and journeys
Every step, spin and mile, measured properly.
StepWheelTools is a shelf of twenty free calculators for the arithmetic of moving: what your steps are worth, what your pace predicts, what your gears produce and what your journeys cost. Each one runs entirely in your browser, shows the method it used, and tells you plainly where its answer stops being trustworthy.
No sign-in, no uploads, nothing leaves this page — the numbers you type are calculated on your own device.
Estimates with their limits statedWorks offline once loadedDark & light
Steps todaylive demo
10,000
Distance7.42 km
Energy358 kcal
Brisk pace10:00 /km
Illustrative figures for an average adult stride — your real ones are one tool away.
The shelves
Five shelves, twenty tools
Everything here is organised the way the questions arrive in life: on foot first, then running, then the body underneath both, then wheels, then the everyday sums that surround all of it. Every tool below is free, instant and private.
Running & Races
Pace, splits, heart-rate zones and training speeds for race day and every day before it.
Body & Energy
The body numbers people quote most — BMI, daily energy, burn rates and body composition.
Cycling, Wheels & Fuel
Gears, cadence and tyre maths for bikes, plus the fuel sums for everything with a tank.
Time & Everyday Maths
Travel time, speed in any unit, exact ages and percentages — the sums that turn up weekly.
A calculator that hides its method has only given you half an answer — the confident half.
That is the whole philosophy of this site in one sentence. Every page here names its formula, states its assumptions and marks the point where the answer becomes a guess. We would rather hand you a range and the reason for it than a single gleaming number that quietly depends on a stride, an activity factor or a maximum heart rate you never chose. You bring the inputs you know; we bring the arithmetic and the honesty about what the arithmetic cannot know.
Category guides
How each shelf thinks
Before the tools, the ideas behind them — five short guides to what each category is really measuring, which figure matters most inside it, and the mistake each one is designed to help you stop making.
Steps & Walking, in depth
Every step statistic you have ever seen — the ring that closes, the streak that must not break — rests on one unglamorous quantity: how far one of your steps actually travels. Step counters are good at counting. They are much worse at knowing what a step is worth, because that depends on your leg length, your speed, the slope under your shoes and whether you are strolling with a coffee or late for a train. The four tools on this shelf exist to close that gap honestly. The stride calculator estimates the length of your step from your height and shows you, in plain numbers, why 10,000 steps is a different distance for a 160 cm walker than for a 190 cm one. The converter then applies that stride to any count you give it, and the calories calculator layers your weight and your pace on top, because energy burn is mostly a story about moving mass over distance.
The walking pace calculator is the quiet overachiever of the shelf. Time any walk over a known distance — the school run, the dog loop, the kilometre markers in the park — and it returns the number that predicts almost everything else: how long the 5 km to the station will take, whether your “brisk” really is brisk by the definitions exercise science uses (below about 10 minutes per kilometre), and how much of a long walk’s slowness is hills rather than fitness. Coaches call pace the master variable because it converts effort into arrival times. Once you know yours at an easy effort and at a hard one, every route in your life becomes estimable, and estimation — not motivation — is what gets people out of the door on dark mornings.
Use these tools together in that order: stride first, then distance, then energy, then pace. And re-measure your stride occasionally. It shortens as walking speed drops and as we age, and a tracker still using the stride of your faster self will keep congratulating you on distances you did not quite walk.
Running & Races, in depth
Running looks simple from the outside and is almost entirely arithmetic on the inside. Pace decides what a race costs; splits decide whether you pay that cost in instalments or all at once at kilometre 32; heart rate decides what the same pace means on a hot day compared with a cold one. The tools on this shelf cover the four calculations runners actually return to. The pace calculator converts any run you have done into pace and speed, then extends it with the Riegel formula — the endurance relationship, published in 1977 and still unbeaten as a one-number model, that predicts how times stretch as distance grows. The split calculator turns a goal time into a per-kilometre plan with even, negative or positive shape, because “run 3:45” is not a plan but “reach halfway in 1:53” is.
The heart-rate zone calculator offers both zone systems in honest use: simple percentages of maximum, and the Karvonen method, which folds your resting heart rate in and usually deserves the trust of anyone who trains more than casually. Zones exist to stop you spending every run in the grey middle — too hard to recover from, too easy to adapt to — and the difference between the two methods is exactly the difference between a generic chart and one that knows your resting pulse is 52, not 70. Finally, the training pace calculator anchors a whole week to a single honest 5K: easy days genuinely easy, tempo at the edge of conversation, intervals at 5K effort, repetitions fast with full recovery.
One warning applies to the whole shelf: every prediction assumes the performance you feed it was real. A Riegel prediction built on a downhill, wind-assisted 10K will happily promise you a marathon you cannot run. Garbage in, gospel out is the failure mode of all sports maths — these tools show their working so you can judge the inputs yourself.
Body & Energy, in depth
Body numbers suffer from a particular kind of fame: everyone knows their BMI, almost nobody knows what it can and cannot say. This shelf is built around that distinction. The BMI calculator gives the number, its band, and — more usefully — the healthy weight range computed for your actual height, because “lose some weight” is not a target but “the range for 176 cm runs from 57 to 77 kg” is. Alongside it sit the energy tools. The BMR & TDEE calculator uses the Mifflin-St Jeor equation, the resting-burn formula that validation studies keep finding closest for most adults, then applies an activity multiplier with its uncertainty stated out loud instead of hidden. The calorie burn calculator prices fifteen activities from published MET values, and the body fat calculator resurrects the US Navy tape method, which turns a neck, a waist and a height into a composition estimate that embarrasses many smart scales.
Together the four tools answer the question people actually bring: how much do I burn, how much should I eat, and is the weight I am losing the right kind? The honest answers are ranges, and these pages present them as ranges — a loss target, a gain target, a protein band — because a single spuriously precise number (“your TDEE is 2,347 kcal”) would be a lie told in a confident font. Bodies also talk back: the three-week weight trend is a better TDEE meter than any equation, and the tools here tell you to recalibrate against it rather than defend the formula.
A note on tone, because this shelf needs one: these are planning instruments, not verdicts. BMI cannot see muscle; the tape cannot see fitness; no equation can see how you feel climbing stairs compared with last spring. Use the numbers to navigate, and let the trend — in weight, in waist, in pace at the same heart rate — be the judge.
Cycling, Wheels & Fuel, in depth
Wheels multiply what legs can do, and they do it through ratios — which makes this the most mathematical shelf on the site and, for riders, the most useful. The gear and cadence calculator works the core relationship: one turn of the cranks turns the rear wheel chainring÷sprocket times, so a gear is fully described by its ratio, its development in metres, and the traditional gear-inch figure that riders have quoted for a century. Add your cadence and it becomes a speed. This is the tool that explains why spinning at 95 rpm in a smaller gear beats grinding at 60 rpm in a bigger one on everything except a sprint finish, and the one to consult before a hilly trip: check that your lowest gear, at a cadence you can actually hold, produces a climbing speed you can balance at. The cycling speed calculator is the after-ride companion — average speed with the 10 km block time that reveals whether you faded or finished strong.
The tyre calculator deals with the number every bike computer quietly depends on. Speed and distance on a sensor-based computer are just wheel revolutions multiplied by a circumference, and the ETRTO size moulded on your sidewall — 47-622 and its cousins — contains that circumference if you know how to read it: bead diameter plus twice the width, times π. Get it from this page after any tyre change, or your computer will keep paying you for the old tyre’s smaller circle.
And because not every wheel in life has pedals, the fuel cost calculator prices road trips the same honest way: consumption, distance, pump price, with round-trip and per-person splits. Garage forecourts are where vague estimates go to become arguments; this page settles them before anyone gets in the car.
Time & Everyday Maths, in depth
Not every calculation in a moving life is about training. This shelf holds the four sums that turn up in kitchens, cars and group chats. The travel time calculator divides distance by a realistic average speed — and spends as much effort warning you about the average as doing the division, because the classic planning error is using the fastest stretch of road as if it were the whole journey. The speed converter translates between km/h, mph, metres per second and knots, and into the inverted world of running pace, where the number goes down as you get faster and a small change means more than it looks. The age calculator does the calendar’s borrowing honestly — exact years, months and days, total days lived, and the countdown to the next birthday — for school cut-offs, race age categories and the morbid pleasure of learning you are eleven thousand days old.
The percentage calculator completes the shelf because percentages are the most mishandled numbers in everyday life. It answers the three shapes every percentage question takes — a percent of a number, a number as a percent of another, and percentage change — and its explanation covers the trap inside the third: a 50% fall followed by a 50% rise does not bring you home, because the second percentage is taken from a smaller base. If you have ever been confused by a headline statistic, the missing question was almost always “percent of what?” This shelf is small on purpose. These are the tools you will use weekly rather than seasonally, and each one is built to be opened, answered and closed in under a minute.
Featured tools
Eight tools, in detail
The eight pages visitors return to most, examined properly: what each one does, the method underneath it, and the edge where its answer runs out. The rest of the shelf is one scroll up.
Steps & Walking
Steps to Kilometres Converter
Your step counter reports a count; this converter turns the count into the distance it represents, using a stride estimated from your height or a stride you measured yourself. It is the first tool most visitors need, because nearly every other number on this site — calories from steps, steps per kilometre, the true length of a 10,000-step day — is downstream of this one multiplication.
How it works. Steps × stride length, with stride estimated at roughly 41.5% of height for the average adult profile. Switch to a measured stride and the same page becomes exact for your own gait: ten steps on flat ground, measured toe to toe, divided by ten.
Where it stops. Stride shortens uphill, in crowds and when you are tired, so a day’s conversion is an estimate with a few percent of give in it — honest for planning, useless for settling bets.
10,000 steps → 7.42 km
Stride used74 cm
In miles4.61 mi
Open tool
Running & Races
Running Pace & Finish Time Predictor
Feed it any finished run and it answers in pace and speed — then keeps going, predicting your finish times for 5K, 10K, the half marathon and the marathon. It is the page to open the night a race result lands, when the only real question is what that result says you could do next, over a distance you have not raced yet.
How it works. Predictions use the Riegel endurance formula (time scales with distance^1.06), fitted on real race results in 1977 and still the standard one-line model. The exponent above 1 is the fatigue tax: doubling the distance always costs more than double the time.
Where it stops. It assumes the training behind both distances is equal. A 5K time will flatter your marathon unless you have done marathon work; treat long predictions as ceilings, not promises.
10K in 52:00 → 5:12 /km
Half marathon prediction1:55:12
Marathon prediction4:00:47
Open tool
Running & Races
Heart Rate Zone Calculator
Five training zones, drawn two ways on the same page so you can see what the choice of method does to your training. The simple system takes percentages of an age-estimated maximum; the Karvonen system works from your heart-rate reserve and shifts every zone to fit the resting pulse you actually wake up with.
How it works. Maximum heart rate is estimated as 220 − age, then Zone 1–5 span 50–100% of it. Karvonen instead reserves: zone heart rate = resting + percentage × (max − resting). Same skeleton, different anchor — and for fit runners the Karvonen zones land noticeably higher.
Where it stops. The 220 − age formula is off by 10 beats or more for many individuals. If a hard race has shown you a higher maximum, trust the race and nudge the age input until the page agrees with it.
Z1 Recovery · 50–60%Z2 Endurance · 60–70%Z3 Tempo · 70–80%Z4 Threshold · 80–90%Z5 Peak · 90–100%
Open tool
Body & Energy
BMR & TDEE Calculator
Two numbers govern every diet that has ever worked: what you burn at complete rest, and what you burn living your actual day. This calculator produces both, then shows the eating targets that follow from them — a steady-loss figure, a lean-gain figure, and the protein range that protects muscle while the scales move.
How it works. Resting burn comes from the Mifflin-St Jeor equation, the formula validation studies find closest to measured values for most adults. Total daily burn multiplies it by an activity factor you choose from plain-language descriptions rather than guesswork labels.
Where it stops. The activity multiplier is the soft spot: self-described ‘moderately active’ days vary by hundreds of calories. The page tells you to calibrate against your three-week weight trend and let the trend overrule the equation.
TDEE 2,612 kcal/day
BMR (at rest)1,685 kcal
Steady loss target2,112 kcal
Open tool
Cycling, Wheels & Fuel
Gear & Cadence Calculator
Every gear on your bike, translated into the four numbers riders actually think in: ratio, gear inches, metres of development, and the speed that gear produces at the cadence you are turning. Slide the cadence and watch the speed answer change while the gear stays the same — the clearest demonstration on the site that the engine matters as much as the gearing.
How it works. One crank turn rotates the rear wheel chainring ÷ sprocket times. Multiply by the wheel’s circumference for development; multiply again by cadence for speed. Gear inches are the historical unit — the diameter of the old penny-farthing wheel the gear is equivalent to.
Where it stops. It models a perfect, lossless drivetrain on a still day. Real speed also pays for wind, gradient and rolling resistance, so read the figure as what the gearing permits, not what the road will grant.
50 × 16 @ 90 rpm → 39.4 km/h
Gear inches84″
Development6.58 m
Open tool
Cycling, Wheels & Fuel
Tyre Size & Circumference Calculator
The two numbers moulded into every tyre sidewall — width and bead diameter, the ETRTO code — quietly determine what your bike computer thinks a kilometre is. This page decodes them into circumference, overall diameter and revolutions per kilometre, and gives you the exact figure to type into the computer’s wheel-size setting.
How it works. Diameter is bead diameter plus twice the tyre width (the tyre stands roughly as tall as it is wide); circumference is that diameter times π. It is an approximation, and the page explains the one-minute rollout test that replaces it with a measurement of your own tyre, at your pressure, under your weight.
Where it stops. Rim width and inflation change the real figure by a percent or two. For odometer honesty across a season that is worth caring about; for a single ride, it is not.
47-622 → 2,246 mm
Overall diameter716 mm
Revolutions per km445
Open tool
Cycling, Wheels & Fuel
Fuel Cost Calculator
The road-trip argument settler. Distance, your car’s real consumption, today’s pump price — and out comes the fuel the trip will drink, what it costs in total, what it costs per kilometre, and what each passenger owes if the ride is shared. A round-trip switch and imperial mpg support are built in because real trips and real cars come in both.
How it works. Litres = distance × consumption ÷ 100 (or the mpg path: miles ÷ mpg × 4.546 litres per gallon). Cost is litres times price. Nothing fancier is needed — the honesty is in the inputs, especially using your car’s own long-term average rather than the brochure figure.
Where it stops. It cannot know about the detour, the roof box or the hour in traffic. Add a tenth for winter and full loads, and treat the per-kilometre figure as the trip’s floor cost, not its whole cost — tyres, wear and tolls live elsewhere.
480 km round trip → 34.6 L
Total cost9,754
Split 4 ways2,439 each
Open tool
Running & Races
Race Split Calculator
A goal time is a wish; a split table is a plan. Choose the distance — 5K to the marathon — set the clock you are chasing, and the page writes your kilometre (or mile) splits under three strategies: metronome-even, the negative split that championship races are won with, and the positive split that hilly courses sometimes force on you.
How it works. Even splits divide the goal by the distance. The negative strategy bends the schedule along a gentle power curve — about 4% of pace surrendered early, repaid late — rather than a single step at halfway, because fatigue does not arrive in one step either.
Where it stops. It assumes a course as flat as your goal is ambitious. On a hilly or windy course, plan by the strategy that matches the course profile, and expect the clock at the exposed sections to look ‘wrong’ while being right.
km 20 · clock 1:46:12km 30 · clock 2:39:40km 40 · clock 3:33:05finish · 3:45:00
Open tool
Anatomy
Every calculator here is laid out the same way
Open any tool on this site and you will find the same three parts in the same three places. That sameness is deliberate: learn one page and you have learned twenty, and there is nothing to dismiss, accept or configure before the tool will work for you.
01 · The question
The tool’s name, the shelf it belongs to, and one paragraph saying plainly what it answers and what it needs from you. Nothing sits above it except the site header. If a page on this site cannot explain itself in that paragraph, the tool was not ready to be published — several candidate tools died at exactly this gate, including a marathon predictor that needed so many caveats it was really an essay wearing a form.
02 · Your numbers
The inputs, in the order you would naturally supply them: the thing you know first at the top, the refinements after. Every field is labelled with its unit in words — centimetres, kilograms, minutes — because the commonest calculator error in the world is a correct number in the wrong unit. Defaults are sensible, recent, real-world values, so the page is already showing you a worked example before you touch anything.
03 · The answer, with its working
The headline result first, large, then the supporting figures around it: the same answer in the other unit, the intermediate quantities, the comparison that makes it mean something. Results update as you type — there is no calculate button to hunt for — and below them each page carries a short section on method and limits: the formula’s name, its assumptions, and the point where you should stop trusting it.
That last panel — method and limits — is the one most calculator sites leave out, and the one we consider non-negotiable. A number without its assumptions is a rumour. Where a formula has a known error band, the page says so in numbers: 220 − age can miss by ten beats; Mifflin-St Jeor lands within about ten percent for most adults; brochure fuel figures understate real driving by ten to twenty-five. You are trusted with the uncertainty because you are the one acting on the answer.
In practice
Whole outings, start to finish
Nobody opens this site wanting a gear-inch figure. They open it wanting to be ready — for a race, a tour, a commute change. These are the three runs visitors describe most, written out in the order the tools actually get used.
A first marathon, planned backwards
- Running Pace & Finish Time PredictorStart from a recent 10K, not a hope. The Riegel prediction gives the ceiling; a first marathon gets planned a few minutes inside it.
- Race Split CalculatorTurn the goal into a negative-split schedule and memorise the three checkpoints that matter: 5K, halfway, 10K to go.
- Training Pace CalculatorAnchor the training weeks to a fresh 5K so the long runs stay easy enough to finish and the tempo work stays honest.
- Heart Rate Zone CalculatorSet the ceiling for long-run effort, so enthusiasm in week two does not spend the fitness week ten was saving for.
A bike tour that has to fit the hills
- Gear & Cadence CalculatorCheck the lowest gear at a climbing cadence of 70 rpm. If it produces a speed you cannot balance at, the cassette changes before the trip does.
- Tyre Size CalculatorFit the wider touring tyres, then read off the new circumference and update the bike computer before the first ride, not after a week of flattering distances.
- Cycling Speed CalculatorUse last tour’s distance and moving time to set a daily average you have actually achieved — loaded, on real roads.
- Travel Time CalculatorTurn daily distance and that average into riding hours, and see whether the itinerary leaves daylight for dinner.
A walking habit that survives winter
- Stride Length CalculatorSet the stride once, honestly, so the tracker’s distances stop being fiction in either direction.
- Steps to Kilometres ConverterTranslate the daily target into distance. “8,000 steps” means little; “5.9 km — the river loop and back” gets walked.
- Walking Pace CalculatorTime the loop once a month. Pace at the same effort is the fitness graph that never lies to you.
- Steps to Calories CalculatorSee what the habit is worth in energy terms — motivation for some, and a guard against eating it all back for others.
Limits
Where each tool stops
The most important text on a calculator site is the part that tells you not to believe it too much. Eight of the limits that matter most, in plain language — the full version sits on every tool page.
Steps to Calories Calculator
The MET values behind it are averages measured on groups. Your personal burn varies with fitness, terrain and how much of the walk was waiting to cross roads — treat the answer as the centre of a range about ±15% wide, and never as a food voucher printed to the kilocalorie.
Heart Rate Zone Calculator
An age-based maximum is an estimate with a wide spread: plenty of healthy 40-year-olds max at 168, plenty at 190. Every zone on the page inherits that spread. A field test or a hard race’s peak reading is better evidence than any formula, including this one.
BMI Calculator
BMI cannot distinguish a kilogram of muscle from a kilogram of fat, and it misreads the very tall, the very short, the elderly and the athletic in predictable directions. It is a screening tool — a reason to look closer, never a diagnosis and never a verdict on an individual body.
Running Pace Predictor
Riegel’s exponent of 1.06 fits trained endurance runners racing comparable distances. It breaks down for sprinters, beginners, and anyone whose marathon training is mostly optimism. Predictions beyond the neighbouring distance should always be discounted a little.
Fuel Cost Calculator
It prices fuel only. A car’s true per-kilometre cost — tyres, servicing, depreciation, insurance — is commonly two to three times the fuel figure, and consumption itself swings with speed, weather and load. Budget with this page, but budget above it.
Gear & Cadence Calculator
The speed shown assumes every watt reaches the road. Drivetrain losses, wind and gradient all take their cut in the real world, so the figure is the gearing’s promise, not the road’s. On a climb, gravity rewrites the answer entirely.
Body Fat Calculator
The Navy method’s error is typically 3–4 percentage points, and worse at the extremes of leanness and obesity, or when fat is carried in unusual places. It tracks change over time far better than it states a level on any single morning.
Age Calculator
Exact ages in years-months-days depend on calendar borrowing, and officialdom does not always agree with it — leap-day birthdays and school cut-offs follow rules, not arithmetic. For anything legal or competitive, confirm which rule the authority uses.
Choosing between lookalikes
Similar numbers, different jobs
Half the confusion in fitness and cycling maths is two quantities that sound interchangeable and are not. Four pairs, separated.
Pace, or speed?
Running Pace Calculator — Minutes per kilometre — time per unit of distance. Runners plan with it because races are measured in distance.
Speed Converter — Kilometres per hour — distance per unit of time. Cyclists, drivers and treadmills talk this language.
The two are inverses, and the conversion is a division, not a swap: halving your pace does not double your speed, it doubles your speed only when the pace exactly halves. If your watch shows one and your plan says the other, convert once, properly, before the run — mid-run arithmetic at threshold effort is nobody’s strength.
Stride, or step length?
Stride Length Calculator — On this site, one step: the distance between successive strikes of opposite feet, estimated from your height.
Steps to Kilometres Converter — Takes that per-step distance and multiplies it by your count, whichever profile you choose.
Pedants reserve ‘stride’ for two steps — same foot to same foot. Trackers, and this site, use the per-step meaning. Whichever definition a device uses, the danger is mixing them: a two-step stride entered as a one-step stride doubles every distance you will ever record.
BMR, or TDEE?
BMR & TDEE Calculator — BMR is the burn of lying perfectly still for a day: the cost of being alive and nothing else.
Calorie Burn Calculator — Prices activity on top of rest — the part of the day you actually choose.
Eat at BMR while living a normal life and you are in a steep deficit whether you meant to be or not. Most ‘my metabolism is broken’ stories are this confusion with better marketing: the equation was fine, the label was wrong.
Gear inches, or development?
Gear & Cadence Calculator — Gear inches — the equivalent penny-farthing wheel diameter. A century of riders quote it, so comparisons across eras work.
Tyre Size Calculator — Development — metres travelled per crank turn — depends on your actual wheel, which is where the tyre page comes in.
The two describe the same gear from different centuries. Inches are portable between bikes without knowing the wheel; development is the truth on your bike, with your tyres, today. Quote inches in the café, plan with development.
Reference
The pace chart, printed out
Most visitors who stay on this page longest are converting between the two dialects of running: speed and pace. This table is the dictionary. Read across from a treadmill speed to the pace it produces and the race times that pace would give you over even splits — the numbers the pace calculator produces live, frozen here for the speeds people ask about most.
| Speed | Pace /km | Pace /mile | 5K | 10K | Half marathon | Marathon |
|---|---|---|---|---|---|---|
| 8 km/h | 7:30 | 12:04 | 37:30 | 1:15:00 | 2:38:14 | 5:16:28 |
| 9 km/h | 6:40 | 10:44 | 33:20 | 1:06:40 | 2:20:41 | 4:41:21 |
| 10 km/h | 6:00 | 9:39 | 30:00 | 1:00:00 | 2:06:37 | 4:13:14 |
| 11 km/h | 5:27 | 8:47 | 27:16 | 54:33 | 1:55:06 | 3:50:13 |
| 12 km/h | 5:00 | 8:03 | 25:00 | 50:00 | 1:45:31 | 3:31:02 |
| 13 km/h | 4:37 | 7:26 | 23:05 | 46:09 | 1:37:22 | 3:14:47 |
| 14 km/h | 4:17 | 6:54 | 21:26 | 42:51 | 1:30:26 | 3:00:53 |
| 15 km/h | 4:00 | 6:26 | 20:00 | 40:00 | 1:24:25 | 2:48:49 |
| 16 km/h | 3:45 | 6:02 | 18:45 | 37:30 | 1:19:07 | 2:38:14 |
| 18 km/h | 3:20 | 5:22 | 16:40 | 33:20 | 1:10:20 | 2:20:41 |
| 20 km/h | 3:00 | 4:50 | 15:00 | 30:00 | 1:03:18 | 2:06:37 |
Two things this table cannot show: fatigue and terrain. It assumes the speed is held from gun to tape, which is exactly what the split calculator is for. It also stops being the right dictionary on hills — a 5:00 kilometre uphill and a 5:00 kilometre downhill are different efforts wearing the same number. For walking, the useful range is the top of the table: most adults walk between 4 and 6.5 km/h, which is 15:00 down to about 9:14 per kilometre, and “brisk” in the research literature begins around the point where the walk starts feeling like a decision — roughly 6 km/h, 10:00 per kilometre, or about 100 steps a minute.
Heart-rate zones at a glance
Zone 1, recovery, 50–60% of maximum: the effort of a walk you could sustain all afternoon, used the day after hard training. Zone 2, endurance, 60–70%: the conversational engine room where most weekly volume belongs. Zone 3, tempo, 70–80%: comfortably hard, phrases rather than sentences. Zone 4, threshold, 80–90%: the fastest pace sustainable for about an hour, and the boundary most training plans are organised around. Zone 5, peak, 90–100%: minutes at a time, in intervals, with full recoveries — seasoning, never the meal. The zone calculator draws these bands on your own maximum and resting rates; this list is only their shared shape.
Tyre sizes you will actually meet
Road tyres cluster at 700c (622 mm bead): 23, 25, 28 and 32 mm widths, circumferences from about 2,096 to 2,155 mm. Gravel moves to 40–50 mm on the same rim or drops to 650b (584 mm) for volume at a similar overall diameter. Mountain bikes run 27.5″ (584 mm) and 29″ (622 mm) with widths of 55–65 mm, where circumference passes 2,300 mm and a size error costs real distance. Whatever the label on the tyre’s shoulder says in inches, the ETRTO pair in millimetres is the measurement to trust — inches on tyres are historical names, not dimensions.
How it's built
Built like a stopwatch, not a funnel
One page, one question
There is no dashboard, no account, no plan to upgrade to. Every tool is a single page that answers a single question and then lets you leave. The business model of most calculator sites is your attention; the model here is that a page which respects your time gets bookmarked, and bookmarks are worth more than minutes.
Your numbers stay yours
Every calculation runs in your browser, in code the page arrived with. Your weight, your dates, your routes are typed into your own machine and computed there — there is no server on this site capable of receiving them, which is a stronger promise than any privacy policy sentence. View the page source if you like; the whole machine is visible.
Formulas with names
Where a calculation rests on published work — Riegel’s endurance exponent, Mifflin-St Jeor, the Navy circumference method, the Compendium’s MET values — the page names it and links the idea to its limits section. Anonymous precision is how calculator sites mislead; a named formula can be checked, argued with and improved on.
Under the hood
The site is hand-written HTML, CSS and JavaScript, assembled by small scripts from a single catalogue of tools — which is why the ticker, the shelves, the mega-menu and the search box can never disagree about what exists here: they are all printed from the same list. Before any version ships, an automated pass walks every page checking internal links, icon references and the wiring between each tool’s form fields and its script, and a second pass reads the visible text looking for the verbal tics of filler. Neither checker is clever. Both are strict, and the build does not proceed while either is complaining.
There is no framework, no bundler and no analytics script, and the fonts are served from this domain rather than called in from elsewhere — partly for privacy, partly because a page about the arithmetic of speed should itself be fast. If you save any tool page to your device it will keep working on a plane, in a tunnel, or anywhere else the network is not.
Ctrl K
Opens from every page on the site, and closes again on Esc. On a Mac it is ⌘ K — the label on the search button adjusts itself to your keyboard.
Every tool here is two keys away
The search palette covers all twenty tools by name, by category and by the job they do. Type “tyre”, “split”, “burn” or “split the fuel” and the list narrows as you type; the arrow keys move, Enter opens. For a site whose entire purpose is getting you to an answer quickly, the fastest route across it had to be a keyboard shortcut rather than a menu — menus are for browsing, and browsing is what you do when the tool has already failed to be found.
Missing
What is not here yet
A tools site should be as honest about its gaps as about its formulas. Some of these are planned, some are waiting on a decision, and two are refusals we expect to keep.
Route elevation
Real pace on real hills needs elevation data, and elevation data lives behind map services this site deliberately does not call. A grade-adjusted pace tool is possible with manual climb entry and may arrive in that form.
Swim and row splits
Per-100 m and per-500 m pace cultures deserve their own pages rather than a runner’s tool with the labels changed. Planned, once the cycling and running shelves stop growing.
Power for cyclists
Wattage estimation needs rider weight, gradient, wind and position — four honest inputs or one dishonest answer. We are still deciding whether the honest version is usable enough to ship.
A training log
Saving your results would need accounts and a database. That trade — your history for our server — is exactly the one this site exists to refuse. Your spreadsheet is a better log than we would build.
Live fuel prices
Prices change by the hour and by the street. A page that guessed yesterday’s price and printed it confidently would be worse than the empty field we give you to fill from the pump in front of you.
Medical clearances
Nothing here can tell you whether a heart rate, a BMI or a training load is safe for you personally. That is a clinician’s job, with your history in front of them. The tools inform; they do not clear.
If the tool you came for is on this list, telling us so genuinely changes the order things get built — requests are read, counted and argued about. The contact page is the way in.
Glossary
The words, defined once
Every term the tools above rely on, defined the way this site uses it. Where the wider world uses a word differently, the definition says so.
Pace
Time taken to cover a unit of distance — minutes per kilometre or per mile. The inverse of speed, and the native language of runners and walkers because races are measured in distance, not time.
Stride length
The distance one step carries you, heel-strike to the other heel-strike. Scales with height and speed; the hidden multiplier inside every step statistic.
Cadence
Steps per minute when walking or running; pedal revolutions per minute when cycling. Same word, same idea — how fast the limbs are turning over.
Riegel formula
The endurance model T2 = T1 × (D2 ÷ D1)^1.06, relating finish times across distances. The 1.06 exponent is fatigue, quantified.
MET
Metabolic equivalent of task: an activity’s energy cost as a multiple of resting. Sitting is 1; brisk walking about 4.3; running at 12 km/h about 11.5.
BMR
Basal metabolic rate — the energy a body uses in a day at complete rest, before any movement is added.
TDEE
Total daily energy expenditure: BMR scaled by daily activity. The calorie level at which weight, on average, holds still.
Heart-rate reserve
Maximum heart rate minus resting heart rate. The Karvonen method sets zones inside this reserve rather than inside the whole range from zero.
Gear inches
A gear expressed as the diameter, in inches, of the penny-farthing wheel it is equivalent to. Bigger number, harder gear, longer history.
Development
The distance a bicycle travels on one full turn of the cranks, in a given gear. Ratio times wheel circumference.
ETRTO size
The tyre standard written as width–bead diameter in millimetres (e.g. 47-622). The only tyre measurement that means the same thing on every brand.
BMI Prime
BMI divided by 25. Expresses body mass index as a fraction of the top of the healthy band, making heights easier to compare.
Short answers
Asked often, answered plainly
No — and not as a policy choice but as an architectural fact. There is no server component to StepWheelTools: the pages are static files, and every calculation happens in JavaScript running in your browser. Your weight, your dates of birth, your race times are typed into your own machine and never transmitted anywhere. Open your browser’s developer tools and the Network tab while you use any tool here, and you can watch the silence for yourself. The only thing the site stores is your light-or-dark theme preference, in your own browser’s local storage, on your own device.
As accurate as the stride you give them. With a measured stride — ten steps, a tape, one division — the conversion is typically within two or three percent on flat ground. With the height-based estimate, allow closer to seven percent either way, because the formula describes an average walker and you are a specific one. Hills shorten real strides, crowds shorten them further, and tired legs shorten them most of all. If a number here ever disagrees with a measured route, believe the route and update your stride.
Because watches and this site are estimating the same invisible quantity from different evidence. A watch sees heart rate, wrist movement and its own proprietary model, and independent testing usually finds watches overestimate energy burn by fifteen to thirty percent, some by much more. This page uses the published MET method — transparent, checkable, and blind to your heart rate. Neither is a measurement; a measurement requires a laboratory mask. For planning meals and comparing activities, the MET figures are the more honest guide; for how hard a session felt, your watch’s heart-rate trace is the better witness.
Yes, with one discipline: treat the TDEE figure as a starting estimate, not a fact. Eat at the loss target the calculator gives you for three weeks, weigh yourself under the same conditions a few mornings a week, and watch the trend. If the trend matches the predicted half-kilo a week, your TDEE was right. If it does not move, your true maintenance is lower than the equation’s guess — lower the target by 150–200 kcal and repeat. That loop, estimate-test-adjust, is how every successful plan actually works; the calculator’s job is to give the loop a sensible first number.
Because of the exponent. Doubling a distance does not double the time: Riegel’s formula raises the distance ratio to the power 1.06, and over marathon distance that small exponent compounds into many minutes. A 40-minute 10K runner is not on for a 2:48 marathon but about 3:06 by the formula — and the formula still assumes marathon-specific training behind it. The gap between the naïve doubling and the Riegel answer is, almost exactly, the physiology of glycogen, heat and accumulated muscle damage. It is not the calculator being pessimistic; it is the distance being honest.
For most riders, most of the time: somewhere between 80 and 95 rpm on flat ground. Below about 70, the force per pedal stroke climbs and knees start paying for what the cardiovascular system should be covering; above 100, beginners tend to bounce and waste energy on coordination. Climbs legitimately drop cadence — 65–75 rpm on a steep gradient in your lowest gear is normal — and sprinting legitimately exceeds 110. Use the gear and cadence calculator to find which gear on your bike holds your chosen cadence at your cruising speed; that gear, not the biggest one, is your home gear.
The circumference figure from the tyre size calculator on this site, in millimetres, for the tyre actually fitted. Enter it after every tyre change: moving from a 25 mm to a 32 mm road tyre adds roughly 50 mm of circumference, and a computer still set for the old tyre will under-record every ride by about two and a half percent — over a 5,000 km year, that is 125 km quietly deleted. If you want the last word in accuracy, do the rollout test described on the tyre page and enter your own measured number instead.
No, and it does not pretend to be once you read its limits. BMI was built from population data in the nineteenth century and cannot see composition: a rugby forward and an inactive person of the same height and weight receive the same score. If you train seriously, read BMI alongside the body-fat estimate from the tape method and your waist measurement. When BMI says ‘overweight’ and the tape says fifteen percent body fat, believe the tape. When both agree, believe them both.
Because the official figure was recorded on a standard test cycle that real traffic rarely resembles, and it typically flatters the car by ten to twenty-five percent. Your dashboard’s long-term average — or two fuel-ups’ worth of your own arithmetic — turns this page from an estimate into a budget. If you only have the brochure number, use it, and then add a tenth before you rely on the answer for money you cannot overspend.
Yes to both. Every page is self-contained: once it has loaded once, the tool works with no connection at all — on a plane, in a tunnel, at a trailhead with one bar of nothing. The layout is built phone-first, because the natural home of a pace chart is a start line and the natural home of a fuel calculation is a petrol station. There is nothing to install and no app to update; bookmark the pages you use and they will simply be there.
Pick a number you know. We will do the rest.
Your steps, your last race, your tyre’s sidewall, your fuel receipt — everything on this site starts from something already in your pocket.