Fitness & Training
4 free calculators & converters. Every tool runs entirely in your browser — nothing you type is uploaded.
Available calculators
One Rep Max (1RM) Calculator
Free one rep max (1RM) calculator. Enter a weight you lifted and how many reps you did to estimate your theoretical 1RM. Supports multiple formulas.
VO2 Max Calculator
Estimate your VO2 max (maximal oxygen uptake) from age, resting heart rate, or distance performance. Cardiovascular fitness indicator.
Pace Calculator
Instantly convert running pace between minutes per mile, minutes per kilometer, miles per hour, and kilometers per hour. Perfect for runners and cyclists.
Race Time Predictor
Predict your 5K, 10K, half-marathon, and marathon times from any recent race using the proven Riegel formula. Works for all distances and paces.