Short, sourced guides that explain the numbers behind our calculators.
The 7 one-rep max formulas, comparedWhere each equation comes from, how they differ, and which to use.How to test your 1RM safelyA step-by-step test-day protocol, and when to estimate instead.Percentage of 1RM and rep-max chartHow percentages map to reps, and how to use them in training.
Calculators
One rep max calculatorEstimate your 1RM from any set, with 7 formulas side by side.Bench press maxBench-specific estimate, rep-max chart and tips.Squat maxSquat 1RM estimate with depth and safety notes.Deadlift maxDeadlift estimate and why rep formulas can miss on pulls.Overhead press maxStrict press estimate with small-jump rounding.Plate calculatorWhich plates to put on each side of the bar.Warm-up calculatorA ramp of warm-up sets, with plates for each.Training max calculatorTraining max and a 4-week percentage wave.My lifts & PRsSaved sets and personal records, stored only on your device.