Calorie & BMR Calculator
Calculate your Basal Metabolic Rate (BMR) — the calories you burn at complete rest — and your Total Daily Energy Expenditure (TDEE) based on your activity level. Uses the Mifflin-St Jeor equation, the most validated formula for adults. Free and private.
Key Capabilities
Mifflin-St Jeor BMR equation
Uses the Mifflin-St Jeor equation (1990), validated in multiple peer-reviewed studies as the most accurate formula for estimating Basal Metabolic Rate in the general adult population.
TDEE across five activity multipliers
Multiplies BMR by an activity factor — Sedentary, Lightly Active, Moderately Active, Very Active, or Extra Active — to estimate Total Daily Energy Expenditure and daily maintenance calorie intake.
Weight loss and gain targets derived automatically
Displays a 500 kcal deficit for 0.5 kg per week loss and a 500 kcal surplus for gradual gain alongside the maintenance TDEE — giving three immediately actionable calorie numbers.
How to Use
Enter age, sex, height, and weight
Fill in all four fields. Metric (kg and cm) and imperial (lbs and ft/in) are both supported — toggle with the unit selector.
Select your weekly activity level
Choose the level that best describes your average week including structured exercise and general daily movement, not just gym sessions alone.
Read BMR, TDEE, and goal calorie targets
Your BMR, maintenance TDEE, and calorie targets for weight loss and gain are all displayed. Consult a dietitian before making large changes to your diet.
Common Use Cases
- People starting a structured fat-loss programmeSomeone beginning a weight-loss journey calculates their TDEE and immediately has a daily calorie target for a sustainable 500 kcal deficit without guessing or relying on generic population averages.
- Personal trainers setting client macrosA personal trainer calculates TDEE for each new client during onboarding and uses it as the baseline for building a macronutrient plan tailored to training volume and body composition goals.
- Dietitians cross-checking patient dietary intakeA dietitian compares a patient's reported calorie intake against their calculated TDEE to assess whether they are genuinely in a deficit or unconsciously eating at maintenance.
Frequently Asked Questions
What is the difference between BMR and TDEE?
BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest to maintain basic physiological functions. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor to account for physical activity. TDEE represents the calories needed to maintain your current weight.
Which calorie formula is most accurate?
The Mifflin-St Jeor equation (1990) is considered the most accurate for estimating BMR in the general adult population, outperforming the older Harris-Benedict equation in multiple validation studies. However, all formulas provide estimates — individual metabolic rates vary by ±200 kcal/day.
How do I use TDEE to lose weight?
To lose approximately 0.5 kg per week, create a daily deficit of 500 kcal below your TDEE. For 1 kg per week, aim for a 1,000 kcal deficit. Always ensure intake stays above 1,200 kcal/day for women and 1,500 kcal/day for men. Consult a dietitian for personalised guidance.
Related Tools
BMI Calculator
Calculate your Body Mass Index (BMI) using metric (kg/cm) or imperial (lbs/inches) measurements. Instantly see your WHO weight category. Free, private, and runs entirely in your browser with no uploads.
Heart Rate Zone Calculator
Calculate your 5 cardiovascular training zones based on your age. Optionally enter your resting heart rate to use the Karvonen (Heart Rate Reserve) method for more personalised zones. Used by athletes, coaches, and cardiologists.
Ideal Body Weight Calculator
Calculate your Ideal Body Weight (IBW) using the three most widely cited clinical formulas: Robinson (1983), Devine (1974), and Miller (1983). Enter height in centimetres and select sex for instant results in kilograms. Used in medication dosing, anaesthesia, and nutrition planning.