Running pace is the time it takes to cover a unit of distance, typically expressed in minutes per kilometer (min/km) or minutes per mile (min/mi). The Riegel formula (1977) — T2 = T1 x (D2/D1)^1.06 — predicts race times across distances with remarkable accuracy from 1,500m to the marathon. For example, a 25:00 5K runner can expect approximately 52:00 for 10K and 1:55:00 for a half marathon.
How to Calculate Running Pace
Running pace is expressed as time per distance unit — minutes per kilometer (min/km) or minutes per mile (min/mi). The formula: Pace = Total Time ÷ Distance. A 50-minute 10K gives you 5:00/km. This calculator works all three ways: enter pace + distance to get finish time, pace + time to get distance, or distance + time to get pace.
Marathon Pace Chart
| Goal Time | Pace/km | Pace/mi | Speed |
|---|---|---|---|
| Sub-3:00 | 4:15 | 6:50 | 14.1 km/h |
| Sub-3:30 | 4:58 | 7:59 | 12.1 km/h |
| Sub-4:00 | 5:41 | 9:09 | 10.5 km/h |
| Sub-4:30 | 6:24 | 10:18 | 9.4 km/h |
| Sub-5:00 | 7:07 | 11:27 | 8.4 km/h |
What are negative splits in running?
A negative split means running the second half of a race faster than the first. Most world records are set with even or slight negative splits. Going out too fast leads to "hitting the wall" — a dramatic pace slowdown in the final kilometers. The split table above helps you plan consistent pacing.
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