How this running pace calculator works
Pace, time and distance are tied together by one simple relationship: pace = time ÷ distance. Rearranged, that also means time = pace × distance and distance = time ÷ pace. Because the three values are linked, knowing any two lets you solve for the third — which is exactly what this calculator does.
Pace is normally expressed as minutes and seconds per mile or per kilometre, while speed is the inverse, expressed as miles or kilometres per hour. To switch units, the tool converts pace with the fixed factor 1 mile = 1.609 km: a min/km pace is multiplied by 1.609 to get min/mile, and divided by 1.609 to go the other way.
Race splits are just your cumulative time at each marker. At an even pace, the split at marker n equals n × your per-unit pace, so the 3rd kilometre at 5:00 min/km lands at 15:00. The table below shows common training paces mapped to finish times for the four standard race distances.
| Pace (min/km) | Pace (min/mile) | 5K | 10K | Half | Marathon |
|---|---|---|---|---|---|
| 4:00 | 6:26 | 20:00 | 40:00 | 1:24:23 | 2:48:47 |
| 4:30 | 7:14 | 22:30 | 45:00 | 1:34:56 | 3:09:53 |
| 5:00 | 8:03 | 25:00 | 50:00 | 1:45:29 | 3:30:59 |
| 5:30 | 8:51 | 27:30 | 55:00 | 1:56:02 | 3:52:04 |
| 6:00 | 9:39 | 30:00 | 1:00:00 | 2:06:35 | 4:13:10 |
| 6:30 | 10:28 | 32:30 | 1:05:00 | 2:17:08 | 4:34:16 |
| 7:00 | 11:16 | 35:00 | 1:10:00 | 2:27:41 | 4:55:22 |
Reference note: predictions assume an even pace held for the full distance and do not account for fatigue, terrain, weather or walk breaks. Use them as planning targets rather than guarantees.
Frequently asked questions
- How do I calculate running pace?
- Pace is time divided by distance. Divide your total running time by the distance to get the time per mile or per kilometre — for example, 25 minutes over 5 km is 25 ÷ 5 = 5:00 min/km.
- What is a good 5K time?
- For many recreational runners, 25 to 30 minutes is a solid 5K goal (about 5:00 to 6:00 min/km). Beginners often start around 35 to 40 minutes, while competitive club runners finish under 20 minutes.
- How do I convert min/km to min/mile?
- One mile is 1.609 km, so multiply your min/km pace by 1.609 to get min/mile. A 5:00 min/km pace is 5.0 × 1.609 ≈ 8.05 minutes, or about 8:03 per mile.
- What pace do I need to run a sub-2-hour half marathon?
- A half marathon is 21.0975 km. To finish under 2 hours (120 minutes) you need to average about 5:41 min/km, or roughly 9:09 min/mile, the whole way.
- How are race splits calculated?
- Splits are your cumulative time at each mile or kilometre marker. At an even pace, the split at marker n is simply n × your per-unit pace.
- How fast should I run a marathon?
- A marathon is 42.195 km. Many first-timers aim for 4 to 5 hours (about 5:41 to 7:06 min/km). A sub-4-hour marathon needs roughly 5:41 min/km, and sub-3-hour needs about 4:16 min/km held throughout.