BMR Calculator

BMR Calculator. Calculate your Basal Metabolic Rate (BMR) — the calories your body burns at rest. Free online BMR calculator for men and women using the Mifflin-St Jeor equation. Supports metric and imperial units.

Instantly calculate your Basal Metabolic Rate with our free online BMR calculator. Enter your gender, age, weight, and height to get your BMR in calories per day — the number of calories your body burns at complete rest.

Our basal metabolic rate calculator uses the Mifflin-St Jeor equation, the most accurate formula recommended by nutritionists and dietitians for healthy adults.

Our BMR calculator for women and BMR calculator for men both run entirely in your browser — no personal health data is ever sent to a server. Switch between metric (kg/cm) and imperial (lbs/in) units with automatic conversion.

Once you have your BMR, pair it with our TDEE Calculator, BMI Calculator, or Ideal Weight Calculator to build a complete picture of your caloric needs and weight management goals.

Frequently asked questions

How do I calculate my basal metabolic rate?

Choose Metric (cm/kg) or Imperial (in/lb), select Male or Female, and enter your Weight, Height and Age. The Basal Metabolic Rate box shows the estimate in calories per day, rounded to a whole number. It is an estimate, not medical or dietary advice.

What formula does this BMR calculator use?

It uses the Mifflin-St Jeor equation: 10 x weight in kg + 6.25 x height in cm - 5 x age in years, then +5 for men or -161 for women. Imperial values are converted to kg and cm first. For example, a 30-year-old man weighing 70 kg at 175 cm gets 1649 calories per day.

Is the BMR calculator different for women and men?

Yes. The Gender switch changes the constant: the female equation subtracts 161 instead of adding 5, so a woman with the same weight, height and age gets a result 166 calories per day lower.

Can I use pounds and inches?

Yes. Select Imperial (in/lb) and enter weight in pounds and height in total inches, for example 69 for 5 ft 9 in. Switching units converts the values already typed, so you do not lose your entries.

What is the difference between BMR and daily calorie needs?

BMR is the energy your body uses at complete rest for breathing, circulation and cell repair. Your total daily energy expenditure (TDEE) is higher because it adds physical activity and digestion; it is usually estimated by multiplying BMR by an activity factor, which this tool does not do.

How accurate is the BMR result?

Mifflin-St Jeor is based on population averages, so an individual's real metabolic rate can differ noticeably, especially for very muscular people, older adults or people with medical conditions. Use the figure as a starting point and consult a healthcare provider or dietitian before changing your diet.

How to use this online tool

BMR Calculator is designed for fast browser workflows when you need to format, validate, convert, decode, encode, generate, or inspect data without opening a heavy desktop app. Start with the input field or visible options, review the result, then copy or download the output for the next step.

Private processing in your browser

BMR Calculator keeps the normal processing step local in your browser. That is useful for code snippets, tokens, documents, configuration values, text samples, and other material that should not be sent to a remote service unless you explicitly choose to share it.

When this tool is useful

Use BMR Calculator for repeatable developer tasks, technical documentation, QA checks, quick conversions, debugging, content cleanup, and internal team workflows. The page focuses on clear inputs, immediate feedback, and output that is easy to reuse in code, reports, tickets, emails, or notes.

Practical tips

Before copying the final result, check important details such as spacing, casing, filenames, encoding, token structure, line breaks, or output format. Small checks prevent mistakes when the result is reused in source code, API requests, documentation, spreadsheets, or shared files.