Swim Pace Calculator: Pace per 100 m or 100 yd

How this swim pace calculator works

This swim pace calculator works out one of three numbers from the other two: your pace per 100, your total time, or your distance. Choose what to solve for, then enter the two values you know. Pace is shown per 100 meters or per 100 yards, the way swimmers usually count it, and the result shows it in both units.

Enter times as minutes and seconds, such as 1:40 for a pace or 25:00 for a swim, or as hours, minutes, and seconds for long swims, such as 1:05:30. Tenths or hundredths are fine, such as 1:31.44. Open Units to switch between meters and yards. The switch sets the unit of the distance and pace you type. It does not convert the numbers already entered, so 1,650 typed for a yards pool stays 1,650 yards.

Swim pace formula: per 100 m and per 100 yd

Swim pace is time divided by distance, scaled to 100 of the same unit. With time in seconds:

pace per 100 = time × 100 ÷ distance. Rearranged, time = pace per 100 × distance ÷ 100 and distance = time × 100 ÷ pace per 100.

Use one unit at a time: a distance in meters gives a pace per 100 meters, and a distance in yards gives a pace per 100 yards. Every step keeps full precision. Only the numbers you see are rounded: times and paces to the nearest whole second, with half a second rounding up, and distances to the nearest whole meter or yard. The substituted formula under the result shows seconds to two decimals.

Meters or yards: converting swim pace

A yard is exactly 0.9144 meters under the international definition. A 100 m length is longer than 100 yd, so the same speed takes more seconds per 100 m than per 100 yd.

pace per 100 yd = pace per 100 m × 0.9144 and pace per 100 m = pace per 100 yd ÷ 0.9144. For distances, meters = yards × 0.9144 and yards = meters ÷ 0.9144.

A pace of 1:40 per 100 m is 91.44 seconds per 100 yd, shown as 1:31. Going the other way, 1:12 per 100 yd is 78.74 seconds per 100 m, shown as 1:19. This converts speed only. It does not adjust for the different number of turns in a 25 yd, 25 m, or 50 m pool.

Swim pace examples

Pace from distance and time: 1,500 m in 25:00 is 1,500 seconds. 1,500 × 100 ÷ 1,500 = 100 seconds, so the pace is 1:40 per 100 m, or 1:31 per 100 yd.

Time from pace and distance: 1,650 yd at 1:30 per 100 yd is 90 × 1,650 ÷ 100 = 1,485 seconds, a total time of 24:45.

Distance from time and pace: 16:40 at 1:20 per 100 m is 1,000 seconds, and 1,000 × 100 ÷ 80 = 1,250 m.

In yards, 1,000 yd in 12:00 is a pace of 1:12 per 100 yd, or 1:19 per 100 m. For a long swim, 3,800 m at 1:45 per 100 m takes 105 × 3,800 ÷ 100 = 3,990 seconds, shown as 1:06:30.

Swim splits for common distances

At an even pace, every 100 takes the same time, so the split for any distance is pace × distance ÷ 100. Under the result, a table lists the time at your pace for common distances, from 50 to 1,500 m or from 50 to 1,650 yd. At 1:40 per 100 m, that is 0:50 for 50 m, 3:20 for 200 m, and 6:40 for 400 m. For a pace per 50, read the 50 row.

These are even-pace times, not predictions. They show what holding one pace would give, not what you would swim in a race over that distance.

Critical swim speed (CSS)

Below the main calculator, a second calculator estimates critical swim speed from two timed swims. Critical swimming velocity is an idea from exercise physiology: in theory, the speed a swimmer could keep up without reaching exhaustion. Wakayoshi and colleagues (1993) proposed estimating it from two all-out swims, 200 m and 400 m:

CSS = (400 − 200) ÷ (T400 − T200) = 200 ÷ (T400 − T200), in meters per second, with both times in seconds. As a pace, CSS pace per 100 m = (T400 − T200) ÷ 2 seconds. For the pace per 100 yd, multiply that by 0.9144.

Example: a 200 m in 2:00 (120 seconds) and a 400 m in 4:20 (260 seconds) differ by 140 seconds, so CSS = 200 ÷ 140 = 1.4286 m/s. The pace is 140 ÷ 2 = 70 seconds, or 1:10 per 100 m and 1:04 per 100 yd.

The 400 m time must be longer than the 200 m time, or there is no result. If your 400 m average pace is faster than your 200 m pace, the result still shows with a note to check both times, because that is unusual for two all-out swims.

In the study, eight swimmers swam both distances at maximal effort. CSS from the two swims was significantly correlated with their mean speed in a 400 m freestyle. When they swam 4 × 400 m at CSS speed, their blood lactate held at a steady level, and at 2% faster it rose progressively. The authors suggest that CSS may correspond to the exercise intensity at maximal lactate steady state. This page reports CSS as an estimate from two swims, not a lab test.

The published method uses meters, so this page asks for 200 m and 400 m times and does not take yard swims for CSS. The CSS pace is still shown per 100 yd, by the same 0.9144 conversion.

What the numbers do not cover

Pace, time, and distance here are arithmetic. They assume one steady pace and do not account for turns, push-offs, starts, stroke, or open-water current, waves, and sighting. For open water or a triathlon swim, enter the course distance as measured; a course that runs long or short changes the pace.

This page does not estimate calories. The calories burned calculator has swimming options by stroke and effort, and the pace calculator covers running pace per km or per mile. This page shows the arithmetic. It does not grade your pace or suggest a workout.

Source

Critical swim speed: Wakayoshi K, Yoshida T, Udo M, Harada T, Moritani T, Mutoh Y, Miyashita M. Does critical swimming velocity represent exercise intensity at maximal lactate steady state? Eur J Appl Physiol Occup Physiol. 1993;66(1):90–95. doi:10.1007/BF00863406. PMID 8425518.

EVR checked the two-swim formula and the study details above against the authors’ published abstract, not the full paper. Pace, time, and distance are definitions and need no source. The yard conversion uses the international yard, 1 yd = 0.9144 m exactly.

Sources last checked: 8 October 2026.

Frequently asked questions