Online Tool Store
Swim Split Time Predictor
Swim Split Time Predictor produces the plan; swimming it in training is what turns it into a strategy. Runs entirely in your browser with no upload and no.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Health & Fitness
Swim Split Time Predictor
Frontend preview — no upload or external service.
Split plan
Even-paced: 6:00 per 250m. Negative split: 6:05 / 5:55. Controlled positive: 5:58 / 6:02.
How the Swim Split Time Predictor works
- Enter the distance and the time you are targeting.
- Choose a strategy — even splits are the most efficient for most swimmers, negative splits the most reliable in a race.
- Practise the plan in training. A split plan you have never swum is a hope rather than a strategy.
The method
Pace is time divided by distance, and split strategy distributes that pace across the swim.
pace per 100 = total time / (distance / 100)
A negative split holds slightly slower than average early and faster late, which costs a little efficiency and reduces the risk of the collapse a fast start produces.
FAQ
Is a negative split better?
For most swimmers it is more reliable. Going out too fast produces a disproportionate slowdown later, so a slightly conservative first half usually gives a faster overall time than an even effort that starts too hard.
Does pool length change the plan?
It changes the times. A 25 m pool has twice as many turns, and push-offs are faster than swimming, so times are typically quicker than in a 50 m pool for the same effort.
What about open water?
Splits are far less reliable — no walls, plus current, sighting and drafting. Plan by effort and stroke rate rather than by clock splits.
How we compare
| Feature | Online Tool Store | A paper log | A subscription health app |
|---|---|---|---|
| Multiple strategies | ✓ | Even only | ✓ |
| Per-length splits | ✓ | ✓ | ✗ |
| No sign-up | ✓ | ✓ | ✗ |
| Nothing uploaded | ✓ | ✓ | ✗ |
Swim Split Time Predictor produces the plan; swimming it in training is what turns it into a strategy.