Swim Stroke Rate Calculator

Work out swim stroke rate instantly with clear inputs, formula shown and shareable results.

About Swim Stroke Rate Calculator

Stroke rate is strokes per minute, and multiplying it by distance per stroke gives swimming speed. 30 strokes in 45 seconds is 40 a minute, so at 1.2 m/s each stroke covers 1.8 m. The stroke index - speed times distance per stroke - is the standard efficiency metric, and rises as technique improves.

Formulas

Stroke rate

rate = strokes / seconds x 60

Stroke index

index = speed x distance per stroke

Worked example

With the default values below, Swim Stroke Rate Calculator returns Stroke Rate of 40.0. Change any input above and every figure here is recalculated in your browser.

Inputs used

Strokes countedminimum 1: 30
Over this many secondsminimum 0.1 s: 45 s
Swimming speedminimum 0.01 m/s: 1.2 m/s

Results

Stroke Rate: 40.0 strokes/min
Distance Per Stroke: 1.800 m
Stroke Index: 2.1600
Time Per Stroke Cycle: 1.500 s

Step by step

1Values used
2Stroke rate
3Stroke index
4Stroke Rate= 40.0 strokes/min
5Distance Per Stroke= 1.800 m
6Stroke Index= 2.1600
7Time Per Stroke Cycle= 1.500 s

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
This is an estimate from population-average equations, not a medical or diagnostic assessment. Individual results vary with genetics, training history and technique. Seek advice from a qualified coach or clinician before making significant changes to training.
This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

This is an estimate from population-average equations, not a medical or diagnostic assessment. Individual results vary with genetics, training history and technique. Seek advice from a qualified coach or clinician before making significant changes to training.

Frequently Asked Questions

Is a higher stroke rate better?

Not on its own. Sprinters use high rates, distance swimmers trade rate for distance per stroke. The product is what determines speed.

What does stroke index measure?

Efficiency. For a given speed, a swimmer covering more distance per stroke is wasting less energy on drag and slippage.