Swimming pace calculator

Swimmers measure pace per 100. Put in your swim and pool length to see your pace, lengths and time per length.

Your details

Your swim pace

2:30

per 100 metres

Per 100 yards2:17
Lengths of a 25 m pool16.0
Per length0:38
At this pace: 400 m / 750 m (sprint triathlon) / 1,500 m10:00 / 18:45 / 37:30
1 mile / 1,900 m / 3,800 m40:14 / 47:30 / 1:35:00
Energy for this swim, front crawl, slow (MET 5.8)68 kcal, about 405 an hour
SWOLFcount your strokes on one length to see your efficiency score

Pool swimmers usually quote pace per 100 m. Turns make pool swims a little quicker than open water. The stroke you pick changes the energy, not the pace.

Race distances

Your pace over longer swims

The result also turns your pace per 100 m into times for 400 m, 750 m (sprint triathlon), 1,500 m, a mile, 1,900 m and 3,800 m (half and full distance triathlon). Holding a pace gets harder the further you go, and open water without walls to push off is usually a little slower.

The working

Time per 100 m

400 m in 10 minutes is 600 ÷ 4 = 2:30 per 100 m. In a 25 m pool that is 16 lengths, about 38 seconds each.

Typical paces

Front crawl, roughly

Swimmer	Per 100 m
Getting started	3:00 and slower
Regular lane swimmer	2:00 to 2:45
Club or triathlon	1:30 to 2:00
Fast club swimmer	under 1:20

Swim better

Easy wins

Breathe out fully under water
Long, relaxed strokes beat fast choppy ones
Short rests between 50s help you hold form
Open water usually swims slower than the pool

Energy and efficiency

Stroke, weight and SWOLF

Energy comes from the 2024 Adult Compendium of Physical Activities: MET for the stroke × weight in kg × hours. Steady front crawl is 5.8 METs, so 10 minutes for a 69.9 kg (11 st) swimmer is 5.8 × 69.9 × 10 ÷ 60 = 68 kcal; the same time at butterfly (13.8 METs) is about 161 kcal.

SWOLF adds your seconds per length to your strokes per length. At 38 seconds a length and 18 strokes, SWOLF is 56, and each stroke carries you about 25 ÷ 18 = 1.39 m. Lower is better, but only compare scores in the same pool and stroke.

Read with care

What this cannot tell you

StrokeBreaststroke is much slower per 100 than front crawl.
Open waterCold, waves and sighting change everything.
SafetyNever swim open water alone.

Questions

Common questions

What is a good 100 m swim time?

For a regular adult lane swimmer, 2 to 2:45 is very common.

How many lengths is a mile?

About 64 lengths of a 25 m pool.

How do I convert yards to metres?

Multiply by 0.9144.

Sources

Last checked 21 October 2026. Spotted something wrong? Tell us and we will fix it.

Before you push on

New to exercise, or got a heart, lung or joint condition? Have a word with your GP or practice nurse first. Stop and get help if you feel chest pain, faintness or unusual breathlessness, and call 999 if it is severe.