Swim Pace Calculator

Convert between swim time, distance and pace per 100 m or 100 yd, build a split sheet for any race, and see what a given pace predicts over every standard event. Metric and imperial pools are both supported.

Distance preset (m)

Custom distance (m)

Stroke

Swim time (mm:ss.hh)

Pace per 100 m (mm:ss)

Show the mirror table in

Times are entered as mm:ss.hh (or h:mm:ss for long events). Switching the stroke adds a typical stroke-efficiency factor to the freestyle pace you enter, so the numbers stay comparable across strokes.

Predicted finish time

25:00.0

1500 m · 60 lengths of a 25m pool · Freestyle

Pace / 100 m: 1:40.0
Pace / 100 yd: 1:31.4
Average speed: 3.60 km/h · 2.24 mph
Even split every 50 m: 0:50.0
Distance in metres: 1500 m

Estimated critical swim speed

1:46.0 / 100 m

CSS is the pace you could hold for about 30–60 minutes. It is normally measured with a 400 m and a 200 m time trial — CSS = (400 − 200) / 2 — but a race pace about 6% quicker than CSS is a fair rule of thumb, which is what is shown here.

Splits per 50 m

Even pacing is fastest in every event except the 50, where a small fade is normal. Bars show each 50; the line is the cumulative race position.

Cumulative and per-segment splits
Distance	Segment	Cumulative	vs even pace
50 m	0:50.0	0:50.0	+0.0s
100 m	0:50.0	1:40.0	+0.0s
150 m	0:50.0	2:30.0	+0.0s
200 m	0:50.0	3:20.0	+0.0s
250 m	0:50.0	4:10.0	+0.0s
300 m	0:50.0	5:00.0	+0.0s
350 m	0:50.0	5:50.0	+0.0s
400 m	0:50.0	6:40.0	+0.0s
450 m	0:50.0	7:30.0	+0.0s
500 m	0:50.0	8:20.0	+0.0s
550 m	0:50.0	9:10.0	+0.0s
600 m	0:50.0	10:00.0	+0.0s
650 m	0:50.0	10:50.0	+0.0s
700 m	0:50.0	11:40.0	+0.0s
750 m	0:50.0	12:30.0	+0.0s
800 m	0:50.0	13:20.0	+0.0s
850 m	0:50.0	14:10.0	+0.0s
900 m	0:50.0	15:00.0	+0.0s
950 m	0:50.0	15:50.0	+0.0s
1000 m	0:50.0	16:40.0	+0.0s
1050 m	0:50.0	17:30.0	+0.0s
1100 m	0:50.0	18:20.0	+0.0s
1150 m	0:50.0	19:10.0	+0.0s
1200 m	0:50.0	20:00.0	+0.0s
1250 m	0:50.0	20:50.0	+0.0s
1300 m	0:50.0	21:40.0	+0.0s
1350 m	0:50.0	22:30.0	+0.0s
1400 m	0:50.0	23:20.0	+0.0s
1450 m	0:50.0	24:10.0	+0.0s
1500 m	0:50.0	25:00.0	+0.0s

Splits per 100 m (15 rows)

100 m1:40.0

200 m3:20.0

300 m5:00.0

400 m6:40.0

500 m8:20.0

600 m10:00.0

700 m11:40.0

800 m13:20.0

900 m15:00.0

1000 m16:40.0

1100 m18:20.0

1200 m20:00.0

1300 m21:40.0

1400 m23:20.0

1500 m25:00.0

What this pace predicts

Holding 1:40.0 per 100 m over the standard events. Real swimmers fade, so treat the 800 and 1500 as optimistic.

50 m

0:50.0

100 m

1:40.0

200 m

3:20.0

400 m

6:40.0

800 m

13:20.0

1500 m

25:00.0

How your pace compares

Reference 100 m freestyle paces (1:40.0 is the pace you entered).

Elite senior0:48.0 / 100 m

you are 52s/100m behind

National age-group (16–18)0:58.0 / 100 m

you are 42s/100m behind

Strong club swimmer1:12.0 / 100 m

you are 28s/100m behind

Recreational club swimmer1:35.0 / 100 m

you are 5s/100m behind

Fit adult, self-taught2:05.0 / 100 m

25s/100m ahead

Beginner front crawl2:45.0 / 100 m

65s/100m ahead

Fastest stroke. Age-group club swimmers typically hold 1:10–1:40 per 100 m; a national-level junior is under 1:05.

Paces and finish times are estimates for general information, not coaching or medical advice. Pool length, turns, drafting and fatigue all move a real result by several seconds per 100.

About this tool

Swim pace is just distance divided by time, but pools are measured in different units: a 25 yd pool is about 9% shorter than a 25 m one, so a yards time is never comparable to a metres time without conversion. This tool does the unit maths both ways, generates 50 and 100 split sheets, projects a pace over every standard event, and places your pace against age-group reference times. Everything runs in your browser.

100% free — no account needed
Runs in your browser
Nothing is uploaded

Frequently asked questions

Is Swim Pace Calculator really free?

Yes. Swim Pace Calculator is completely free on PureBrowser — every feature, with no account, no trial, and no credit card.

Does Swim Pace Calculator upload my data?

No. Swim Pace Calculator runs entirely inside your browser, so anything you type, paste, or open stays on your own device.

Do I need to sign up or install anything?

Neither. There is no account and nothing to download — open the page and Swim Pace Calculator is ready to use on desktop or mobile.

Does Swim Pace Calculator work offline?

Once the page has loaded, yes. All of the processing happens locally in your browser, so it keeps working without a connection.

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