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Free Online BMR & Calorie Calculator (TDEE)

Enter your sex, age, height, weight, and activity level. You get estimated BMR (calories at rest), maintenance calories (TDEE), and simple targets for mild weight loss or gain.

Sex
30
175
75

Daily calories (estimate)

BMR (at rest)1,699 kcal
Maintenance (TDEE)2,633 kcal
Mild weight loss (−500)2,133 kcal
Mild weight gain (+500)3,133 kcal

Activity factor: ×1.55. Not for children, pregnancy, or medical diets without professional guidance.

Related: BMI calculator · Salary calculator

How BMR and daily calories are estimated

BMR (basal metabolic rate) is the energy your body uses at rest for breathing, circulation, and basic functions. TDEE (total daily energy expenditure) adds activity on top—that is closer to calories you burn in a typical day.

This tool uses the Mifflin–St Jeor equation, a common clinical estimate for adults. We multiply BMR by an activity factor (1.2 sedentary up to 1.9 very active) to get maintenance calories.

Results are estimates—not medical advice. Muscle mass, health conditions, and pregnancy can change needs. Pair with our BMI calculator for weight category screening.

Worked examples

Real problems you might enter in the calculator above, with short walkthroughs.

  • Woman, 35, moderate activity

    Illustrates how activity multiplier raises calories above BMR.

    ProfileFemale · 35 yrs · 165 cm · 68 kg · moderateTDEEBMR ~1,400 kcal · maintenance ~2,200 kcal

  • Man, 30, desk job

    Sedentary factor 1.2 keeps TDEE closer to BMR.

    ProfileMale · 30 yrs · 180 cm · 82 kg · sedentaryTDEEBMR ~1,800 kcal · maintenance ~2,150 kcal

  • Mild weight loss target

    A 500 kcal/day deficit is a common planning shortcut (~0.5 kg / 1 lb per week).

    ProfileMaintenance 2400 kcalTDEEAbout 1,900 kcal/day (−500)

  • US units

    Same formulas after converting to metric internally.

    Profile5 ft 10 in · 180 lb · male · activeTDEESwitch to US units for feet, inches, and pounds

Frequently asked questions about the BMR calculator

  • What is BMR?

    BMR is the calories your body burns at complete rest. It does not include walking, workouts, or digestion—only baseline life functions.

  • What is TDEE?

    TDEE is total daily energy expenditure—BMR scaled up for your activity. Maintenance calories are often set near TDEE when you want to hold weight steady.

  • Which formula does this BMR calculator use?

    Mifflin–St Jeor (1990), widely used in fitness apps and diet planning for adults.

  • How many calories should I eat to lose weight?

    A common starting point is maintenance minus about 500 kcal per day, which this tool shows as mild weight loss. Individual needs vary; adjust based on progress and professional advice.

  • Is BMR the same as calories burned on my watch?

    Wearables estimate total burn (closer to TDEE) using movement and heart rate. BMR here is a formula-based rest estimate—they will not match exactly.

  • Is this calorie calculator free?

    Yes. Calculations run in your browser with no signup.