# Race Time Predictor

From your last race to your next goal.

URL: https://shortformkit.com/race-time-predictor/
Updated: 2026-10-13

The Riegel formula assumes you slow down a little as the distance grows. It works best between 3 km and the marathon and assumes you trained for the longer distance.

**Formula:** T2 = T1 × (D2 ÷ D1)^1.06

Results are estimates for general information, not medical or financial advice.

## How it works

1. **Enter your values** The result updates as you type.
2. **Switch units if needed** Metric or US units, where it applies.
3. **Read the result** Nothing is stored or sent anywhere.

## FAQ

**Is it free?**
Yes. No account, no limits.

**Is my data stored?**
No. The calculation happens in your browser and nothing is sent to a server.


Source: Shortform Kit (https://shortformkit.com/race-time-predictor/). Free, no login.