About HealthFitCalculators

HealthFitCalculators is a free collection of health and fitness calculators built to give you fast, accurate numbers and the context to understand them. Most calculators online hand you a figure with no explanation. We pair every result with plain-language guidance so you actually know what to do next.

What we offer

• BMI Calculator — body mass index with the full WHO category scale.
• BMR Calculator — the calories your body burns at complete rest.
• Calorie Calculator — daily energy needs (TDEE) plus goal targets.
• Body Fat Calculator — the U.S. Navy circumference method.
• Ideal Weight Calculator — four classic clinical formulas.
• Macro Calculator — protein, carbs and fat from your calorie target.

Our approach

The formulas we use are well-established, peer-reviewed equations such as Mifflin-St Jeor for metabolic rate and the U.S. Navy method for body fat. Every calculation runs entirely in your browser — nothing you type is sent to a server. We don't ask you to register, and the tools are free to use.

An important note

These calculators are educational tools that estimate population-level averages. They are not a substitute for professional medical advice, diagnosis, or treatment. Always talk to a qualified healthcare provider before making significant changes to your diet, exercise, or health routine. See our Terms & Medical Disclaimer for details.

Get in touch

Questions, corrections, or suggestions for a calculator we should add? Visit our contact page — we read everything.