Fitness Calculators

Free science-backed calculators to help you reach your fitness goals. Calculate your calories, BMI, body fat, macros, and more.

Choose Your Calculator

Nine science-backed tools, each with the formula explained and the research behind it cited. Every result can be shared, printed, exported to PDF, or saved to your progress tracker.

TDEE Calculator

Calculate your Total Daily Energy Expenditure (TDEE) and maintenance calories.

BMI Calculator

Calculate your Body Mass Index to assess whether your weight is healthy.

Body Fat Percentage Calculator

Estimate your body fat percentage using the US Navy method.

Macro Calculator

Get your daily protein, carbs, and fat targets based on your goals.

One Rep Max Calculator

Estimate your maximum lift for any exercise based on weight and reps.

Ideal Weight Calculator

Find your ideal weight range using four established medical formulas.

Biological Age Calculator

Estimate your biological age from longevity markers like resting heart rate, sleep, and waist-to-hip ratio.

Workout Template Generator

Generate a weekly training split tailored to your available days and goal.

Fiber Analyzer

Search any packaged food for its real fiber content and build a day that hits your fiber goal.