Calorie Calculator
Estimate your daily calorie needs (TDEE) based on age, sex, height, weight, and activity level — using the Mifflin-St Jeor equation.
What is Calorie Calculator?
A calorie calculator estimates how many calories you burn each day so you can plan your eating. It starts from your Basal Metabolic Rate (BMR) — the calories you burn just staying alive at rest — and multiplies it by an activity factor to give you your Total Daily Energy Expenditure (TDEE).
Eat roughly your TDEE to maintain weight. Eat 500 calories below to lose about 1 pound per week, or 250 above to gain about half a pound per week. These are estimates — individual metabolism varies.
Formula
This calculator uses the Mifflin-St Jeor equation, the most accurate widely-used BMR formula for adults:
- Men: BMR = 10×kg + 6.25×cm − 5×age + 5
- Women: BMR = 10×kg + 6.25×cm − 5×age − 161
TDEE = BMR × activity factor (1.2 sedentary → 1.9 extra active).
A deficit of 3,500 calories ≈ 1 pound of body fat, so a daily 500-calorie deficit = ~1 lb/week.
Worked example
A 30-year-old man, 5'9" (69 in), 170 lb, moderately active:
- Weight: 77.1 kg, Height: 175.3 cm
- BMR = 10(77.1) + 6.25(175.3) − 5(30) + 5 ≈ 1,722 cal/day
- TDEE = 1,722 × 1.55 ≈ 2,669 cal/day to maintain
- ~2,169 cal/day to lose 1 lb/week
How to use this calculator
- Pick your sex and enter your age.
- Choose imperial (pounds and inches) or metric (kg and cm) units and enter weight and height.
- Pick the activity level that best describes your weekly routine — be honest; most people overestimate.
- Use the TDEE number as your maintenance target, then subtract or add calories to lose or gain weight at a sustainable rate.
Frequently asked questions
How accurate is the Mifflin-St Jeor equation?
It predicts BMR within roughly ±10% for most adults and is considered the most accurate of the commonly used formulas (better than Harris-Benedict and Katch-McArdle for people of unknown body fat). Your actual metabolism may vary due to genetics, muscle mass, thyroid function, and medications.
Why does my weight loss stall even when I eat at a deficit?
As you lose weight, your BMR drops (smaller body = less fuel needed). You also adapt metabolically — NEAT (fidgeting, small movements) decreases. Recalculate your TDEE every 10–15 lb lost and adjust intake. Also check actual intake honestly — tracking errors of 20–30% are common.
Is 1,200 calories safe for weight loss?
1,200 calories is often cited as a floor for women and 1,500 for men to avoid nutrient deficiencies and metabolic slowdown. If the calculator suggests you would need to eat below that, move more instead of eating less, or choose a slower rate of loss.
Should I count macros or just calories?
Calories drive weight change. Macros (protein, carbs, fat) drive body composition, satiety, and performance. Most people do well with ~0.7–1.0 g of protein per pound of lean body mass, then filling the rest with a mix of carbs and fat to taste.