Race Time Predictor

Predict a race time from another distance (Riegel).

Known distance

Known time

Target distance

Predicted time 110.32

Predicted pace (min/km) 5.229

Formula: T₂ = T₁ × (D₂ ÷ D₁)^1.06

Step-by-step with your numbers:

1. Values used:

2. Known distance = 10

3. Known time = 50

4. Target distance = 21.098

6. Predicted time = 110.32

7. Predicted pace = 5.229min/km

Did we solve your problem today?

Predict your time at a new distance from a recent race (Riegel's formula).

The math behind it

T₂ = T₁ × (D₂ ÷ D₁)^1.06. The 1.06 exponent reflects slowing over longer distances.

10 km in 50 min → half marathon ~1:48.

Accurate?

Best for distances reasonably close to your known race, with proper training.