Running pace calculator
Pace, speed and finish time. Pace zones from threshold
Pace and time
Enter a time or a pace
| 5 km | 25:00 |
| 10 km | 50:00 |
| 21.1 km | 1:45:29 |
| 42.2 km | 3:30:59 |
Assumes the same pace throughout, with no stops
Each kilometre at a constant pace
| Km | Time from start |
|---|
Everything is calculated in your browser. Your numbers stay on your device
Pace zones
The pace that matches an estimate of your critical running speed. It is the anchor for the zones. How to find it
| Zone | % of threshold | Pace, min per km |
|---|---|---|
| Z1Easy, recovery | up to 70 | slower than 7:09 |
| Z2Easy, endurance | 70 to 82 | 7:09 to 6:06 |
| Z3Moderate, tempo | 82 to 95 | 6:06 to 5:16 |
| Z4Hard, around threshold | 95 to 101 | 5:16 to 4:57 |
| Z5Hard, above threshold | 101 and above | 4:57 and faster |
How we calculate
Speed in km/h is 3600 divided by the pace in seconds per kilometre. Time over a distance is the pace multiplied by the number of kilometres. A half marathon is 21.0975 km and a marathon is 42.195 km, with no rounding.
Every calculation assumes the same pace from start to finish with no stops. It is the time at a constant pace. It does not tell you what you will actually run.
Pace zones are built from your threshold pace with the TriCoo table. The bounds are set as a share of speed: 70, 82, 95 and 101 percent of the speed at threshold. They turn into pace by dividing the threshold pace by that share. A bound between zones belongs to the harder zone. More about zones on the Training zones page.
Common questions
What pace do I need for a 4-hour marathon?
About 5:41 per kilometre, if you hold it evenly the whole way with no stops. Enter 4:00:00 in the Time field and pick 42.2 km.
How do I convert pace to speed?
Divide 60 by the pace in minutes. A pace of 5:00 per kilometre is 12 km/h, and 6:00 is 10 km/h. The calculator does this both ways for you.
Why does my watch show a different pace?
The watch measures distance with GPS, and GPS makes errors, especially in cities and forests. The watch also averages pace over the last few seconds. The calculator uses the exact distance.
What is threshold pace?
It is the pace that matches an estimate of your critical running speed. TriCoo builds zones from it. You can find it with a field test, as described on the Threshold tests page. It is not your marathon pace or the average pace of an ordinary run.
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