Running pace calculator

Your pace per kilometre and race predictions for 5K, 10K, half and full marathon.

How the predictions work

Race times use Riegel's formula, which scales your time by distance to the power of 1.06. It assumes you have trained for the longer distance, so treat a marathon prediction from a 5K as a best case.

For easy runs, go 60 to 90 seconds per km slower than your 5K pace. You should be able to talk in full sentences.