This predictor estimates how fast you might finish a race at one distance based on a recent result at another distance. It uses the Riegel formula, a well known endurance model that assumes your time scales with distance raised to the power 1.06, reflecting the slowdown that comes with longer efforts. Enter the distance and finish time of a recent race, then the target distance you want to predict, and it returns the projected time along with the average pace it implies. It works for any pair of distances, so you can project a 5k time up to a half marathon or scale a 10k down to a mile. Everything is calculated locally in your browser. Predictions assume similar conditions and appropriate training for the longer distance, so treat the output as a realistic guide rather than a guarantee.
It uses the Riegel formula, which scales your known time by the distance ratio raised to the power 1.06 to account for slowing over longer distances.
It works best when the new distance is not far from your recent race and when your training suits that distance, so treat it as a guide.
Yes. You enter a recent race and the target distance, and it estimates your finish time for that distance.
This predictor estimates how fast you might finish a race at one distance based on a recent result at another distance. It uses the Riegel formula, a well known endurance model that assumes your time scales with distance raised to the power 1.
Yes. Race Finish Time Predictor is completely free, with no sign-up and no usage limits.
Yes. Race Finish Time Predictor runs in any modern web browser. There is nothing to download or install.
Yes. Race Finish Time Predictor runs entirely on your device in your browser, so nothing you enter is uploaded to a server.