A 10K takes ten times your kilometer pace. Fifty minutes is 5:00/km. An hour is 6:00/km. Seventy minutes is 7:00/km. The course is 10.000 kilometers, or 6.214 miles.
10K pace chart
| Pace /km | Pace /mile | 10K | Halfway (5 km) |
|---|---|---|---|
| 4:00 | 6:26 | 40:00 | 20:00 |
| 4:30 | 7:15 | 45:00 | 22:30 |
| 5:00 | 8:03 | 50:00 | 25:00 |
| 5:30 | 8:51 | 55:00 | 27:30 |
| 6:00 | 9:39 | 1:00:00 | 30:00 |
| 6:30 | 10:28 | 1:05:00 | 32:30 |
| 7:00 | 11:16 | 1:10:00 | 35:00 |
Halfway is a useful check because it is a 5K. If you want 55:00, you should be near 27:30 at 5 km, not 25:00. A 25:00 halfway means you ran the first half at 5:00/km and now need the second half to be slower, or you are heading for a 50:00 finish instead. Build the full marker list in the 10K pace calculator or the split calculator.
Do not multiply a mile pace by 6
6.214 miles × 10:00 per mile is 1:02:08, not 1:00:00. Using 6 miles instead of 6.214 drops the time by about two minutes at that pace. Metric pace avoids the fraction: 6:13/km × 10 km is the same 1:02:08. The min/km converter is the unit step if the plan is in miles and the race bib is in kilometers.
A 10K is not two identical 5Ks
If your 5K best is 25:00, a 50:00 10K is the doubled clock and it is usually a little fast. The race time predictor applies a small slowdown and lands nearer 52 minutes for that 5K. Use the doubled time only as a lower bound. How long a 5K takes has the shorter table if you are still choosing the 5K goal.
Once the 10K time is chosen, the pace page is enough. The formula is the finish time divided by 10. Cutting 5 minutes off a 10K is that same division: 30 seconds per kilometer, whatever the starting clock.