Swim Pace & CSS Calculator
Two swimming calculators in one. Critical swim speed (CSS): from a 400 m and a 200 m time trial, computes your sustainable threshold pace per 100 m and five training zones around it. SWOLF: adds strokes and seconds per length into the classic swimming-golf efficiency score.
Read the full guide to this tool
Results
Notes
- Swim both CSS test efforts all-out with full rest between them, 400 m first; pacing errors flatten the result.
- SWOLF only compares like with like: same pool length, same stroke.
- Educational estimate for sport and training purposes, not professional coaching or medical advice.
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