About 5K pace
A 5K race is exactly 5 kilometers, which equals 3.10686 miles (since one kilometer is 0.621371 miles). "Pace" is how long it takes you to cover one unit of distance, and it is the reciprocal of speed. This calculator takes a single input — your 5K finish time — and reports the average pace you held per kilometer and per mile, your average speed in km/h and mph, and the even-pace split you would need to hit that time.
The formulas
Convert your finish time to seconds, then divide by the distance:
- Pace per km = finish time ÷ 5
- Pace per mile = finish time ÷ 3.10686
- Speed (km/h) = 5 ÷ (finish time in hours)
- Speed (mph) = 3.10686 ÷ (finish time in hours)
Because a mile is longer than a kilometer, your per-mile pace is always a larger number than your per-km pace — about 1.609 times larger. So a 5:00/km pace is roughly 8:03/mile, not the other way around.
Worked example
Suppose you finish a 5K in 25 minutes (1,500 seconds). Pace per km = 1,500 ÷ 5 = 300 seconds = 5:00/km. Pace per mile = 1,500 ÷ 3.10686 = 482.8 seconds ≈ 8:03/mile. Speed = 5 km ÷ (1,500/3,600 h) = 12.00 km/h, or 3.10686 ÷ 0.41667 = 7.46 mph. To run 25:00 evenly you would pass each kilometer marker at 5:00, 10:00, 15:00, 20:00, and finish at 25:00.
Common 5K reference points
- 20:00 — 4:00/km, 6:26/mile, 15.0 km/h
- 25:00 — 5:00/km, 8:03/mile, 12.0 km/h
- 30:00 — 6:00/km, 9:39/mile, 10.0 km/h
- Elite men (~12:35 world record) — about 2:31/km, or 23.8 km/h
Pacing strategy
Even pacing or a slight negative split (running the second half marginally faster than the first) produces the best 5K results for most runners. The most common execution mistake is starting too fast: the first kilometer feels easy on fresh legs, but a 10–15 second overshoot early often costs 30+ seconds over the final two kilometers as fatigue sets in.