Smart pacing wins races. This Swim Time Split Calculator breaks any target time into even splits or negative splits (faster second half) so you can plan your race strategy or structure training sets. Choose your pool course, event distance, and target time — then decide how aggressively you want to negative-split.
Split Calculator
Break your target time into per-lap splits
Formats: ss.hh, m:ss.hh, or h:mm:ss.hh
How much faster each subsequent lap (or second half) should be
Enter a time to see splits...
Understanding Split Strategies
Even Splits
Every lap at exactly the same pace. The simplest and most sustainable strategy, ideal for longer-distance events like the 800m and 1500m.
Negative Splits
Swim the second half faster than the first. Physiologically efficient — builds aerobic capacity early, then accelerates. Used by elite distance swimmers.
Descending
Each lap progressively faster. Great for training sets and building race-end speed. The most aggressive pacing strategy.
When to Use a Split Calculator
- Race planning: Decide your target split for each 50m or 25m leg before stepping on the blocks.
- Training sets: Give swimmers specific pace targets for descending sets, broken swims, or pace 100s.
- Goal setting: Work backwards from a target time to see what each lap needs to look like.
- Post-race analysis: Compare your actual splits against an ideal pacing model to identify where you gained or lost time.
How the Split Calculator Works
- 1Enter your target total time and select the course and event distance.
- 2We calculate the number of laps based on pool length.
- 3We distribute the total time across laps using your chosen split strategy and the delta slider.
- 4Each lap split and cumulative time is displayed so you can study and copy your pacing chart.