Running Calculators & Tools
Free interactive tools to help you plan your training, predict race times, and optimize your performance. Pick a calculator to get started.
Pace Calculator
Calculate your pace per mile or km, predict your finish time, or find your distance. Plan your race-day splits and training targets.
Open tool →Race Time Predictor
Enter a recent race result to predict your times at the 5K, 10K, half, and marathon — plus the training paces to get there.
Open tool →Hydration Calculator
Estimate your daily and during-run fluid needs, adjusted for body weight, run duration, and weather conditions.
Open tool →Looking for more training resources? Check out our training plans and running articles.