Free Fitness Calculators

Science-backed calculators for people who lift. No ads, no sign-up.

Calorie Calculator for Lifters

Daily calories and macros to cut, maintain or bulk, with training-day vs rest-day targets.

Ideal Weight Calculator for Lifters

People's Choice, BMI range, classic IBW formulas and a muscle-aware (FFMI) ideal weight.

BMI Calculator

Body mass index, healthy weight range, and a body fat check for muscular lifters.

How Strong Am I?

Your squat, bench and deadlift percentiles vs 340,000+ raw powerlifters, plus your Dots score.

One-Rep Max & RPE Calculator

Estimate your 1RM from any set, with a percentage table and a full RPE chart.

Body Fat Calculator

US Navy tape-measure method: body fat %, category, fat and lean mass.

Maximum Muscular Potential Calculator

How much muscle you can build naturally: Casey Butt, FFMI and Berkhan estimates.

Barbell Plate Calculator

Enter a weight and see exactly which plates go on each side, in lb or kg.