Fitness & Sports
Free fitness and sports performance calculators for one-rep max, VO2 max, heart rate training zones, race time prediction, Wilks score, and swim pace. Built for athletes and coaches.
Fitness & Sports tools available
One-Rep Max Calculator
FFMI Calculator
Plate Calculator
Calories Burned Calculator
Heart Rate Zone Calculator
Running Pace Calculator
Protein Intake Calculator
Steps Calculator
Race Time Predictor
VO2 Max Calculator
Wilks Score Calculator
Train Smarter With Performance Data
Whether you are programming strength blocks, building an aerobic base, or chasing a race PR, the right numbers make every session count. Our fitness calculators use proven sports-science formulas — Epley and Brzycki for one-rep max, Karvonen for heart rate zones, and Riegel for race time prediction — to turn your results into clear training targets.
All calculations run locally in your browser — your training data stays private. Free to use, no sign-up required — use the results to plan loads, paces, and training intensity with confidence.