Running Pace Calculator
Returns your running pace in min/km and min/mile from any distance-and-time pair. Also predicts finish times at standard race distances using the Riegel formula — a useful sanity check before locking in a race-day plan.
If you skip this, we use a unisex average.
Running Pace, Split, and Race Time
For runners, the same pace-distance-time triangle applies, plus a few race-specific conversions. The calculator also computes even splits for common race distances so you can pace accurately from 5 km to the marathon.
- pace
- Minutes per km or mile, at a given effort.
- split
- Cumulative time at each km or mile marker on a race.
- speed
- 60 ÷ pace<sub>min/km</sub> = km/h.
50 ÷ 10 = 5:00 min/km. At 12 km/h that is 200 m/min, and 200 ÷ 1.25 m = 160 spm — right in the elite/sub-elite cadence band recommended by Daniels and Cavanagh.
Source: Riegel, "Athletic Records and Human Endurance", American Scientist, 1981 (exponent 1.06).
The Riegel Race Time Formula
Riegel's endurance formula predicts race times at one distance from a performance at another. It works within ±2 % for distances between 3 km and the marathon, which is why it shows up in most training-plan calculators.
- T₁, D₁
- Known race time and distance (e.g., a recent 10 km).
- T₂, D₂
- Target race time and distance.
- 1.06
- Fatigue exponent from Riegel 1981. Slightly higher (1.08) for marathoners.
50 × (21.1 ÷ 10)^1.06 = 50 × 2.21 ≈ 110.5 min = 1:50:30. The half pace lands at about 5:14/km — 14 s/km slower than 10 km pace.
Source: Riegel, "Athletic Records and Human Endurance", American Scientist, 1981 (exponent 1.06).
Running Intensity Zones
Five zones derived from heart-rate and lactate research. Zone definitions follow Daniels' VDOT framework; the axis shows pace in minutes per kilometer.
Source: Daniels Running Formula, 3rd ed. (2014); Billat lactate thresholds.
Race-Pace Predictions From a 10 km
Riegel projections assuming equal training for each distance. In practice marathon times run 3–5 % slow of the model without specific endurance work.
| 10 km | 5 km | Half marathon | Marathon |
|---|---|---|---|
| 35:00 | 16:52 | 1:17:15 | 2:41:00 |
| 40:00 | 19:17 | 1:28:20 | 3:05:00 |
| 45:00 | 21:41 | 1:39:20 | 3:28:00 |
| 50:00 | 24:06 | 1:50:30 | 3:51:30 |
| 55:00 | 26:30 | 2:01:30 | 4:14:30 |
| 60:00 | 28:55 | 2:12:30 | 4:38:00 |
| 70:00 | 33:44 | 2:34:40 | 5:24:30 |
Source: Computed with Riegel exponent 1.06 (Riegel, "Athletic Records and Human Endurance", American Scientist, 1981 (exponent 1.06).).
Target Running Cadence
Cavanagh's 1984 analysis of the 1984 LA Olympic marathon put every male finisher in the 175–185 spm band. Recreational runners benefit from raising cadence 5–10 % above their default.
Source: Cavanagh, IJSM 1984; Heiderscheit et al., MSSE 2011 (cadence and impact loading).
Common Race Time Benchmarks
How quickly various milestone finishes correspond to a training pace.
Sub-30 5 km
A common first milestone. Pace: 5:59/km (9:39/mi). Weekly mileage rarely needs to exceed 25 km.
Sub-50 10 km
The mid-pack recreational target. Pace: 5:00/km. Typical runner has 12–16 weeks of consistent training.
Sub-2 half marathon
The iconic half-marathon finish. Pace: 5:41/km (9:09/mi). Median finish time at large US half marathons.
Easy Pace vs. Threshold Pace
The two paces that matter most in training. Get them right and the rest follows; get them wrong and training stalls.
Easy / aerobic pace
60–75 % HRmax
- Feel
- Full sentences, could sing a chorus
- Typical pace
- 80–90 s/km slower than 10 km pace
- Cadence
- 160–170 spm
- Volume
- 70–80 % of weekly km
Threshold pace
85–90 % HRmax
- Feel
- Short sentences only, "comfortably hard"
- Typical pace
- 10–15 s/km slower than 10 km pace
- Cadence
- 175–185 spm
- Volume
- 10–20 min sustained, 1×/week
Reference tables
Running pace quick reference
| Pace | km/h | mph | Zone |
|---|---|---|---|
| 7:00 min/km | 8.6 | 5.3 | Recovery |
| 6:00 min/km | 10.0 | 6.2 | Easy |
| 5:30 min/km | 10.9 | 6.8 | Marathon |
| 4:45 min/km | 12.6 | 7.8 | Threshold |
| 3:45 min/km | 16.0 | 9.9 | VO₂ max |
Zones based on Daniels VDOT framework.
Mile splits for common paces
| Pace (min/km) | 5 km total | 10 km total | Half | Marathon |
|---|---|---|---|---|
| 4:00 | 20:00 | 40:00 | 1:24:24 | 2:48:48 |
| 5:00 | 25:00 | 50:00 | 1:45:30 | 3:30:00 |
| 6:00 | 30:00 | 1:00:00 | 2:06:36 | 4:13:12 |
| 7:00 | 35:00 | 1:10:00 | 2:27:42 | 4:55:24 |
Assumes even pacing. Add 10–20 seconds per km for realistic marathon finish.