Free Online Calorie Calculator
Estimate your daily calorie needs with the Mifflin-St Jeor equation and an activity factor.
Uses the Mifflin-St Jeor equation for BMR. Calorie needs are estimates — consult a healthcare provider or dietitian for personalized guidance.
to maintain
What is Calorie Calculator?
A calorie calculator estimates how many calories your body needs each day. It first calculates your Basal Metabolic Rate (BMR) — the energy you burn at rest — using the Mifflin-St Jeor equation, then multiplies it by an activity factor to find your Total Daily Energy Expenditure (TDEE). From there it applies a calorie offset for losing, maintaining, or gaining weight.
How to use it
- Choose metric or imperial units and enter your sex, age, height, and weight.
- Select the activity level that best matches your typical week.
- Choose a goal: lose weight, maintain, or gain weight.
- Review your daily calorie target, plus your BMR and maintenance (TDEE) values.
Mifflin-St Jeor equation
BMR (men) = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5. BMR (women) = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161. TDEE = BMR × activity factor (1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 active, 1.9 very active). Target = TDEE + goal offset (−500 lose, 0 maintain, +500 gain).
Frequently asked questions
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest just to stay alive. TDEE (Total Daily Energy Expenditure) multiplies BMR by an activity factor to estimate the calories you actually burn in a day, including movement.
It uses the Mifflin-St Jeor equation, which is widely considered the most accurate formula for estimating BMR in healthy adults without specialized lab equipment.
To lose about one pound per week, you need a daily deficit of roughly 500 calories, since a pound of body fat is about 3,500 calories. This calculator subtracts 500 from your maintenance calories for the weight loss goal.
Sedentary means little or no exercise; light is 1–3 days a week; moderate is 3–5 days; active is 6–7 days; and very active is daily intense exercise or a physical job. Pick the level that reflects a typical week.
Calorie needs are estimates and vary based on muscle mass, genetics, and health conditions. Use the result as a starting point and adjust based on your progress, ideally with guidance from a healthcare provider or dietitian.
Yes. Switch to imperial to enter your height in feet and inches and your weight in pounds. The calculator converts them internally to run the Mifflin-St Jeor equation.
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