Swim Pace Calculator
Turn a swim distance and time into pace per 100 metres and per 100 yards, speed, and the time for a 400 m, 750 m or 1,500 m at that pace.
Your 100 m pace, and what a triathlon swim takes at it.
How the swim pace calculator works
Swimmers measure pace per 100 metres (or per 100 yards in yard pools). Divide your time by the distance in hundreds and you have it; the calculator also projects the pace over the common triathlon swim distances so you can plan a race.
Pool and open-water paces differ — no walls to push off, sighting, currents — so expect an open-water swim to run 5–10% slower than the same pace in a pool.
Formula: pace per 100 = time ÷ (distance ÷ 100)
Worked examples
| Inputs | Pace per 100 m | Note |
|---|---|---|
| 1,000 m in 20:00 | 2:00 /100 m | 2:00 per 100 m |
| 400 m in 7:20 | 1:50 /100 m | 1:50 per 100 m |
| 1,000 yd in 18:00 | 1:58 /100 m | yards converted to metres |
FAQFrequently asked questions
What is a good pace per 100 m?
Around 2:00 is a solid fitness-swimmer pace; 1:30 is strong club level; elite swimmers race 1,500 m at close to 1:00 per 100 m.
How do I convert yards to metres?
A yard is 0.9144 m, so a 25-yard pool is 22.86 m. A 100-yard pace is about 9% faster than the same time per 100 m.
Why is open water slower?
No walls to push off, sighting breaks your stroke, and currents or chop add resistance. Allow 5–10% on your pool pace when planning a triathlon swim.
How long is an Ironman swim?
3.8 km (3,800 m). At 2:00 per 100 m that is 1 h 16 min; the cut-off is usually 2 h 20 min.
Where these figures come from
- Riegel PS, "Athletic records and human endurance", American Scientist 1981 — T2 = T1 × (D2 ÷ D1)^1.06
- Cooper KH, "A means of assessing maximal oxygen intake", JAMA 1968 — the 12-minute run test
- Ainsworth BE et al., Compendium of Physical Activities (2024 update) — MET values by activity
- OpenPowerlifting — DOTS coefficients (Tim Konertz, 2019) — the DOTS polynomial used for scoring
- Naismith's rule (1892) as used by UK and Australian walking bodies — 1 hour per 5 km plus 1 hour per 600 m of ascent
- Australian Institute of Sport — national sports-science body
Last checked: September 2026. Formulas are fixed by their published sources; the MET values come from the Compendium of Physical Activities.