Swim Pace Calculator

Common questions

How do I calculate swimming pace per 100 metres?

Divide elapsed time by distance in metres, then multiply by 100. A 1,500 m swim in 30 minutes gives a pace of 2 minutes per 100 m. The calculator also shows the equivalent pace per 100 yards.

Can I calculate total time from a known pace?

Yes. Choose pace as the known input and enter pace per 100 m or 100 yd. Total time is pace multiplied by distance divided by 100, after converting distance to the pace basis. For example, 400 m at 1:30 per 100 m takes 6 minutes.

Are a length and a lap the same thing?

Terminology varies, so this calculator defines a length as one pool crossing and a lap as two lengths, there and back. It shows complete counts and any remaining distance separately. A 1,500 m swim in a 25 m pool is 60 lengths or 30 two-length laps.

What happens when distance is not a multiple of pool length?

The calculator retains the partial final length and shortens its split duration proportionally. For example, 112 m in a 25 m pool is four full lengths plus 12 m. Custom split intervals also retain their final partial segment.

Can I mix metres and yards?

Yes. Set the swim-distance, pool and pace-basis units independently. Calculations use the exact conversion 1 yard = 0.9144 metres. Changing an input unit reinterprets its unchanged number. Both per-100 outputs are calculated from the same average speed.

What time formats and limits are supported?

Enter positive seconds, minutes:seconds or hours:minutes:seconds, with up to three decimal places in seconds. Clock seconds and the minute field in an hours clock must be below 60. A time or pace input may be up to seven days. Distances accept six decimal places and values up to 1,000,000; split tables support up to 10,000 rows.

Do the splits account for turns or rest?

No. Splits distribute supplied time at a constant average pace. They do not predict achievable performance or prescribe training. If your supplied elapsed time includes rests, the calculated pace includes those rests too; no separate adjustment is made.

Why might rounded split times not add to the total?

Each split and cumulative time is calculated as an exact fraction before rounding to the nearest millisecond. Adding separately rounded segment times can differ from the displayed total. Very small positive times or converted distances may round to zero. CSV includes exact millisecond fractions and every split, including rows beyond the current table page. Inputs stay local and are not automatically saved.