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BMR & Calorie Calculator

Estimate daily calorie needs.

Sex
— cal/day BMR (at rest)
— cal/day Maintenance (TDEE)
— cal/day Mild weight loss (−500)
— cal/day Mild weight gain (+500)

Enter your sex, age, height, and weight to estimate your daily calorie needs.

Disclaimer: This calculator provides general estimates and is not medical advice, a diagnosis, or a diet plan. Calorie needs vary with body composition, health, and lifestyle. Consult a qualified healthcare professional or registered dietitian before making changes to your diet.

Free online BMR and calorie calculator

This BMR calculator estimates your Basal Metabolic Rate — the calories your body burns at complete rest — and your Total Daily Energy Expenditure (TDEE), the maintenance calories you need each day once activity is factored in. It uses the Mifflin–St Jeor equation, one of the most accurate formulas for healthy adults, and works in either metric or imperial units. Enter your details and every number updates live, entirely in your browser, so your information stays private on your device.

How to calculate your calorie needs

  1. Choose Metric or Imperial with the toggle.
  2. Select your sex and enter your age in years.
  3. Enter your height and weight in the chosen units.
  4. Pick the activity level that best matches a typical week.
  5. Read your BMR, maintenance calories, and mild loss and gain targets.

BMR versus TDEE explained

Your BMR is what you would burn lying still all day. Multiplying it by an activity factor gives your TDEE, or maintenance calories — the amount that keeps your weight steady. To lose weight gently, aim for roughly 500 calories below maintenance; to gain, add about 500. These are estimates, so adjust them based on real-world progress over a few weeks.

More health calculators

Pair this with our BMI calculator to see whether your weight sits in a healthy range for your height, or the ideal weight calculator to estimate a target weight. Every tool on the site is free, needs no sign-up, and runs completely in your browser.

Frequently asked questions

What is BMR and how is it calculated?

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to keep essential functions going, such as breathing, circulation, and cell repair. This calculator uses the Mifflin–St Jeor equation: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + s, where s is +5 for men and −161 for women. It is widely regarded as one of the most accurate BMR formulas for the general population.

What is the difference between BMR and TDEE?

BMR is what you burn at rest. TDEE (Total Daily Energy Expenditure), also called maintenance calories, is your BMR multiplied by an activity factor that accounts for daily movement and exercise. TDEE is the number of calories you need each day to keep your weight the same, so it is the figure most people use when planning their diet.

Which activity level should I choose?

Pick the option that best matches a typical week. Sedentary (×1.2) means little or no exercise; Lightly active (×1.375) is light exercise 1–3 days; Moderately active (×1.55) is moderate exercise 3–5 days; Very active (×1.725) is hard exercise 6–7 days; and Extra active (×1.9) is very hard exercise or a physical job. When unsure, choose the lower option to avoid overestimating your needs.

How many calories should I eat to lose or gain weight?

A pound of body fat is roughly 3,500 calories, so a daily deficit or surplus of about 500 calories works out to around one pound per week. This tool shows a mild weight-loss target (TDEE − 500) and a mild weight-gain target (TDEE + 500) as a starting point. These are estimates — adjust based on real-world results and professional guidance.

Is this calorie calculator accurate?

The Mifflin–St Jeor equation gives a solid estimate for most healthy adults, but everyone is different. Factors such as muscle mass, genetics, hormones, and medical conditions all affect your true metabolism, so treat the results as a well-informed starting point rather than an exact figure.

Does this calculator store my data?

No. Every calculation happens locally in your browser using JavaScript. Your age, height, weight, and other details are never uploaded, saved, or shared, so the tool is completely private and free to use.

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