6 free calculators

Free calculators for strength and endurance training

Fast, accurate and free. Every formula is sourced, and nothing you type leaves your browser.

Strength

Load the bar, pick your working weights and compare totals.

See exactly which plates to load on each side of the bar.

Estimate your 1RM from any hard set, then pick weights by reps and RPE.

Compare your total across body weights with every major formula at once.

Lean mass, calories and protein for building muscle.

Find your fat-free mass index and how close you are to the natural muscular limit.

Calories and protein to lose fat while building muscle.

Energy cost of rucking, hiking and loaded walks.

Calories burned walking with a weighted pack, by speed, incline and terrain.