Swimming SWOLF calculator
SWOLF — “swim golf” — scores your stroke efficiency: add the strokes you take for one pool length to the seconds it takes. A lower score means you are covering the distance with less effort. It shows your SWOLF, a 25 m–normalised score to compare pools, and a rating.
Related tools
All Running & endurance tools →Need SWOLF per 25 m, SWOLF score, Rating? The Swimming SWOLF calculator derives it from Strokes per length, Time per length (seconds), Pool units, Pool length in one step. For instance, with Strokes per length = 20, Time per length (seconds) = 22, Pool units = Metres and Pool length = 25 it returns SWOLF per 25 m = 42, SWOLF score = 42 and Rating = Good.
How to use it
- Enter your values: Strokes per length, Time per length (seconds), Pool units, Pool length.
- Read the result instantly: SWOLF per 25 m, SWOLF score, Rating.
Frequently asked questions
How does the Swimming SWOLF calculator work?
It takes Strokes per length, Time per length (seconds), Pool units and Pool length and derives SWOLF per 25 m, SWOLF score and Rating from them. The calculation is live as you type, so the result updates on every change.
Which values does the calculator ask for?
4 values: Strokes per length, Time per length (seconds), Pool units and Pool length. Nothing else is required — no account, no file upload.
What does a typical calculation look like?
With Strokes per length = 20, Time per length (seconds) = 22, Pool units = Metres and Pool length = 25, the calculator returns SWOLF per 25 m = 42, SWOLF score = 42 and Rating = Good. Those figures come from running this exact tool, so you can reproduce them by entering the same values.
How much does the result change with different inputs?
It moves a lot. Using Strokes per length = 40, Time per length (seconds) = 44, Pool units = Yards and Pool length = 50 instead, SWOLF per 25 m goes from 42 to 45.9 — which is why it is worth testing a few scenarios rather than trusting a single figure.
Which “Pool units” option should I choose?
You can pick between « Metres » and « Yards ». Each one changes what the calculator works out, so switch and compare — the default is « Metres ».
What does it give for smaller values?
Scaled down to Strokes per length = 10, Time per length (seconds) = 11, Pool units = Metres and Pool length = 13, SWOLF per 25 m comes out at 40.4. The relationship is worth checking at both ends before you rely on a single result.
When would I actually use this?
Preparing a race: the pace a target time needs, the splits to hold it, and the training zones that sit under it — on foot, and equally on a bike or in a pool, where the same session is measured in watts or in a hundred-metre split instead.
What is the most common mistake?
Scaling a time linearly to a longer distance. A marathon is not two half-marathons; race predictors use an exponent around 1.06 precisely because fatigue is not proportional.
How accurate is it, and what are the limits?
SWOLF = strokes + seconds for one length. The 25 m figure rescales it to a 25 m pool: 1 yd = 0.9144 m, so a 25 yd length is 22.86 m and does not score the same.
What is the difference between the Swimming SWOLF calculator and the Swimming pace calculator?
This one returns SWOLF per 25 m and SWOLF score; the Swimming pace calculator returns Pace per 100 and Speed. That is the whole difference — open the one whose figure you need.