Smart tools for smart runners
A fast, accurate toolbox to compute pace, plan your next race and progress. No signup required, 100% free.
Pace calculator, race predictor, HR zones, VO₂max, calories and splits. Simple, accurate tools for runners.
- Pace calculator - Convert pace, time and distance in min/km or min/mi with automatic splits.
- Race time predictor - Predict your 5K, 10K, half and full marathon times from a recent race (Riegel).
- Heart rate zones - Compute your 5 heart rate zones using the Karvonen (HR reserve) method.
- VO₂max estimation - Estimate your VO₂max from a race time (Daniels & Gilbert).
- Calories burned - Estimate calories burned from weight, duration and intensity (MET method).
- Split planner - Build a per-km pacing plan (even, negative or progressive splits).