Swim Pace Formula
Swim pace is time per 100 m. Open-water and pool times don't translate directly — open water adds 5–15 sec per 100 m depending on conditions, sighting, and chop.
Formula
Copy the exact expression or work through it step by step below.
pace_per_100m = total_time_seconds × 100 / total_distance_m Variables
pace_per_100m
Pace per 100 m
Seconds (or min:sec) per 100 meters. Standard swim pace unit. Pool swim 1:30/100m is moderate, 1:15/100m advanced, sub-1:00 elite.
total_time
Elapsed time
Seconds for the swim set. Convert minutes by × 60.
total_distance
Distance covered
Meters (or yards). 1 yard = 0.9144 m. Pool pace in a 25-yard pool is ~9% faster than in a 25-meter pool.
Step By Step
- 1
Time the full swim set in seconds.
1,500 m in 27:30 = 1,650 seconds.
- 2
Divide by total distance, multiply by 100.
1,650 × 100 / 1,500 = 110 sec per 100 m.
- 3
Convert seconds to minutes:seconds for readability.
110 sec = 1:50 per 100 m.
- 4
For open-water predictions, add a conditions surcharge: +5 sec calm flatwater, +10 sec moderate chop, +15+ sec ocean conditions or strong current.
Calm open-water predicted pace: 1:55 per 100 m.
Worked Example
1,500 m pool swim in 27:30
Distance (m)
1,500
Total time
27:30
pace = 1,650 × 100 / 1,500 = 110 sec/100m = 1:50/100m
Pool pace 1:50 per 100 m. Open-water equivalent in calm conditions: roughly 1:55 per 100 m.
Common Variations
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Sources & References
- Wakayoshi K et al. A simple method for determining critical speed as swimming fatigue threshold in competitive swimming — International Journal of Sports Medicine (1992)
- Maglischo EW. Swimming Fastest — Human Kinetics