Tool roadmap
Running Pace & Split Calculator
Convert pace, speed and finish time, then build cumulative splits.
Race Time Predictor
Estimate equivalent 10K, half-marathon and marathon performances with appropriate limitations.
Training Zone Calculator
Create usable running heart-rate and pace zones plus cycling power zones.
Race Fueling Calculator
Build a time-based carbohydrate, fluid and gel schedule.
More than a widget
All four calculators are live. Each tool explains what the result means, which assumptions it uses, when it becomes unreliable and how to apply it safely.