Know your pace before the gun goes off.
Put in two of finish time, distance and pace. Pace Notes gives you the third, in miles and kilometers, with the clock you should see at every checkpoint.
Four lanes, four calculators
- 1Running pace calculatorKnow two of time, distance and pace, and get the third. Miles and kilometers side by side.
- 2Race time predictor (Riegel formula)One recent race in, predictions for the mile, 5K, 10K, half and marathon out, with honest warnings.
- 3Split calculator: even and negative splitsA split for every mile or kilometer, the clock time you should see, and where halfway falls.
- 4Treadmill pace converter: mph to min/mile and km/hType a speed or a pace. Get mph, km/h, min/mi and min/km, plus the full 4 to 12 mph chart.
Race distances, exactly
A marathon is 42,195 meters, which is 26.2188 miles. Rounding to 26.2 shaves about 0.02 miles off the course and makes every pace chart a few seconds too optimistic. These are the distances every Pace Notes calculator uses.
Sources: World Athletics (marathon and half marathon), NIST Handbook 44 (1 mile = 1,609.344 m). How pace is calculated.
| Race | Meters | Miles | At 9:00/mi |
|---|---|---|---|
| Mile | 1,609.344 m | 1.0000 mi | 9:00 |
| 5K | 5,000 m | 3.1069 mi | 27:58 |
| 10K | 10,000 m | 6.2137 mi | 55:55 |
| Half marathon | 21,097.5 m | 13.1094 mi | 1:57:59 |
| Marathon | 42,195 m | 26.2188 mi | 3:55:58 |
Guides
- Treadmill pace conversion chart: mph to minutes per mileConvert treadmill speed from 4 to 12 mph into pace per mile, km/h and pace per km, with the speed to set for common paces and the 1% incline rule.
- Negative splits: how to run the second half fasterWhat a negative split is, how big the gap should be, and mile-by-mile tables for a 4:00 marathon and a 25:00 5K, computed with exact race distances.
- The Riegel formula explained: predict your race timeT2 = T1 × (D2/D1)^1.06. How Peter Riegel's race time formula works, worked examples from 5K to marathon, and where its predictions break down.
- 5K pace chart: finish times from 18 to 40 minutesPace per mile and per km for 5K goals from 18:00 to 40:00, with mile-by-mile splits and a simple plan for pacing your first or fastest 5K.
- Marathon pace chart: sub-3, 3:30, 4:00, 4:30 and 5:00Pace per mile and per km for the classic marathon goals, plus the clock you should see at 5K, 10K, halfway, 30K and 20 miles.
- How to calculate running pace (per mile and per km)Pace is time divided by distance. Here is the formula, three worked examples, the mile-to-km conversion and the exact race distances to use.