Swim pace calculator
Enter how far you swam, in meters or yards, and how long it took. The calculator gives your pace per 100 m and per 100 yd, your speed, and the time the same pace would take over 400 m, a sprint, Olympic, half or full triathlon swim, or any distance you type.
Runs in your browser: nothing you enter is sent anywhere.
How to use
- Enter the distance you swam and choose meters or yards.
- Type the time as minutes and seconds (30:00) or hours, minutes and seconds (1:05:30).
- Read your pace per 100 m and per 100 yd at the top.
- Change the distance to predict to see how long a race or a set would take at the same pace. The standard triathlon distances are listed below it.
How it works
Speed = distance ÷ time, with yards converted to meters first (1 yd = 0.9144 m). Pace per 100 m = 100 ÷ speed, pace per 100 yd = 91.44 ÷ speed, and the time for any distance = distance ÷ speed. Paces are shown to a tenth of a second, longer times to the second.
Example
You swim 1500 m in 30:00, which is 1800 seconds.
- Speed: 1500 ÷ 1800 = 0.833 m/s, or 3 km/h.
- Pace: 100 ÷ 0.833 = 120 s, so 2:00.0 per 100 m and 91.44 ÷ 0.833 = 109.7 s, so 1:49.7 per 100 yd.
- At the same pace 3.8 km takes 3800 ÷ 0.833 = 4560 s = 1:16:00.
Tips
- Use a swim of at least 400 m for your pace: a single fast length mostly measures your push-off.
- For training zones from a time trial, the swim CSS calculator works out critical swim speed from a 400 m and a 200 m swim.
- Count your lengths carefully: one missed length in a 25 m pool changes a 1500 m pace by almost two percent.
Frequently asked questions
How do I calculate my swim pace per 100 m?
Divide your time in seconds by the distance in meters and multiply by 100. 1500 m in 30 minutes is 1800 s ÷ 1500 × 100 = 120 s, so 2:00 per 100 m. The calculator does this for you and also converts to yards.
What is the difference between pace per 100 m and per 100 yd?
A yard is 0.9144 m, so 100 yd is shorter than 100 m and the same speed gives a faster-looking number per 100 yd. 2:00 per 100 m equals about 1:49.7 per 100 yd. Short-course pools in the US are often 25 yards long, so check which unit your pool uses.
Can I predict my triathlon swim time?
The calculator multiplies your current pace over each distance, so it shows the time if you could hold that pace. Over a longer swim most people slow down, and open water adds sighting, waves and no walls to push off, so treat the projection as a best case.
Why is my pool pace faster than in open water?
Every wall gives you a push-off and a short glide, which a lake or the sea does not. Wetsuits work the other way and usually make you faster. Compare pool times with pool times and open-water times with open-water times.