These are free tools for the decisions that come up while you are actually training — how heavy to go next week, which plates to grab, what your zones should be. Each one runs entirely in your browser: nothing is stored, and none of them ask for an email address.
More calculators are being added over time. If there is one you keep wishing existed, tell us and it will go on the list.
One Rep Max Calculator
Estimate your one-rep max from any weight and rep count using the Epley and Brzycki formulas, with a full percentage chart. For lifters running percentage-based programs.
Open calculator → StrengthPlate Loading Calculator
Work out exactly which plates go on each side of the bar for any target weight, in kg or lb. For anyone tired of doing bar math mid-session.
Open calculator → EnduranceVO2 Max Calculator
Estimate your VO2 max from a recent race result or field test. For runners tracking aerobic fitness over a training block.
Open calculator → EnduranceHeart Rate Zone Calculator
Turn your max and resting heart rate into personalised training zones. For anyone doing zone 2, threshold, or polarised training.
Open calculator →