What you can calculate
Find your pace from distance and time, find a finish time from distance and pace, or predict your times for other race distances from a recent result.
Race predictions
Predictions use Riegel's formula, which works best for 5K to marathon and assumes comparable training for the longer distance.
Frequently asked questions
What's a good marathon pace?
It varies widely: around 6:00 per km (about 9:40 per mile) gives roughly a 4:13 marathon.
How do I convert min/km to min/mile?
Multiply by 1.609. A 5:00 per km pace is about 8:03 per mile.
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