SWOLF & stroke efficiency calculator
Calculate SWOLF, stroke rate, distance per stroke and pace from one pool length. Choose your counting method for consistent swimming comparisons.
Results
Enter your values or try the example.
How it works
Time one pool length and count your strokes using a consistent method. SWOLF adds that time in seconds to the entered count. Stroke rate is count × 60 ÷ time; distance per stroke is pool length ÷ count. Cycle mode uses the same equations with cycles as the counting unit. Distance per stroke includes the effect of your push-off and glide; it is not a measurement of propulsion alone. Use the same stroke and pool for comparisons.
For worked examples and help interpreting your score, read Apple Watch SWOLF explained.
Measure one complete pool length
Enter the pool length, the time for one crossing and the count recorded during that same crossing. Choose individual arm entries or full cycles to label your counting method. The calculation uses the count you enter; selecting a method does not automatically double or halve it. Keep that choice consistent between comparisons.
Example: 25 m in 22 seconds
With a count of 20, SWOLF is 22 + 20 = 42. The calculated rate is about 54.55 counts per minute, distance per count is 1.25 metres and pace is 1:28 per 100 metres. The meaning of a count follows your selected method, so arm-entry and full-cycle results should not be mixed.
Compare time and count together
A lower SWOLF alone does not establish a faster swim. Taking 24 seconds with 17 counts produces 41, which is lower than 42 but takes two seconds longer. Compare the same pool length, stroke and counting convention, and keep the time visible alongside the score. This tool describes a single length; it does not correct a watch’s counting errors or assess technique from the numbers alone.