Free Fitness Calculators

Accurate, science-backed tools for health, nutrition, and performance. No sign-up. No ads. Just results.

Body Composition

Calculate your Body Mass Index and see which category you fall in.

Estimate body fat percentage using the US Navy tape-measurement method.

Find your Basal Metabolic Rate — calories burned at complete rest.

Total Daily Energy Expenditure — your real daily calorie burn based on activity.

Find the right calorie intake for weight loss, maintenance, or muscle gain.

Calculate your ideal protein, carbohydrate, and fat targets from your calories and goals.

How much water should you drink per day? Get a personalised hydration target.

Estimate your 1RM for any lift using the Epley formula and set training loads.

Convert between pace, speed, and finish time for any race distance.

Calculate your 5 heart rate training zones from your maximum heart rate.