Fitness Goal 4U toolkit

Body Composition Calculators

Understand weight, body fat, metabolic baseline, and health-risk markers. Every tool is free, private, responsive, and designed to explain its result clearly.

10 specialized tools
01Body Composition

BMI Calculator

Calculate your Body Mass Index and healthy weight range.

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02Body Composition

BMI Prime Calculator

Compare your BMI with the upper threshold of the healthy range.

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03Body Composition

BMR Calculator

Estimate the calories your body burns at complete rest.

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04Body Composition

TDEE Calculator

Estimate your total daily energy expenditure and maintenance calories.

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05Body Composition

Body Fat Calculator

Estimate body fat percentage with the U.S. Navy circumference method.

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06Body Composition

Lean Body Mass Calculator

Estimate fat-free body mass from weight and circumference measurements.

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07Body Composition

FFMI Calculator

Assess muscular development relative to your height.

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08Body Composition

Ideal Weight Calculator

Compare estimated ideal weights across established clinical formulas.

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09Body Composition

Waist-to-Height Ratio Calculator

Screen central adiposity with your waist-to-height ratio.

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10Body Composition

Fitness Age Calculator

Estimate fitness age from resting heart rate, BMI, and age.

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Private calculations, clearer decisions

All calculations run in your browser. We do not require an account or store your measurements. Results are educational estimates and should be interpreted within your health and training context.

Learn about our methodology →