Race Split Calculator
Set a race distance and a goal time and get your split for every kilometre or mile, with the choice of even pacing, a negative split (faster second half) or a positive split.
Your numbers
Hours : minutes : seconds
| Split | Split time | Clock |
|---|
Result
Your result appears above and updates as you type.
How it works
Even splits are the fastest way to run most races because the energy cost of running rises steeply with speed: a fast early kilometre buys seconds at a price paid back with interest later. The negative-split option in this calculator eases you in about 4% slower than average at the start and brings you home about 4% faster at the end, following the gentle curve most world records are actually run on.
The positive-split column exists because some courses demand it — a hilly first half, a downhill start, or a point-to-point wind. Use it to plan honestly for the course you have rather than the course you wish you had.
Good practice & limits
- Memorise three numbers, not forty: your 5K split, halfway split and 10K-to-go split. The rest follows.
- Check the clock at splits, not between them. Glancing every 200 metres turns pacing into panic.
- Build a 1–2% cushion into the goal if the course is crowded — weaving around runners adds distance.