Calorie Calculator (TDEE)
Find how many calories you should eat a day to lose weight, maintain, or build muscle — based on your total daily energy expenditure. Want the macro split too? Use the macro calculator.
Your personalized macros appear here
Fill in your details and tap Calculate my macros to see your daily calorie, protein, fat, and carb targets.
A calorie calculator estimates how many calories you should eat per day to reach your goal. It first finds your maintenance calories (TDEE) — the amount that keeps your weight stable — using the Mifflin-St. Jeor equation, then adjusts: eat about 500 calories below your TDEE to lose roughly a pound a week, at your TDEE to maintain, or a few hundred above to gain muscle. Enter your age, sex, height, weight, activity level, and goal above for your personalized number.
How the calorie calculator works
Your body burns calories even at rest — that's your Basal Metabolic Rate (BMR). The Mifflin-St. Jeor equation estimates it from your age, sex, height, and weight. Multiplying BMR by an activity factor gives your TDEE, the total you burn in a day.
To lose weight you eat below your TDEE; to gain you eat above it. The size of the gap sets the pace — a 500-calorie daily deficit is about a pound a week. Knowing the number is easy; hitting it every day is the hard part, which is where CarbMeNot comes in — snap a photo and it logs your calories automatically.
Frequently asked questions
- How many calories should I eat a day?
- It depends on your size, activity, and goal. This calculator estimates your maintenance calories (TDEE), then subtracts for weight loss or adds for muscle gain. A common weight-loss target is about a 500-calorie daily deficit, which is roughly a pound a week.
- What is TDEE?
- TDEE stands for Total Daily Energy Expenditure — the total calories your body burns in a day, including your resting metabolism and activity. Eat below your TDEE to lose weight, at it to maintain, and above it to gain.
- How is my calorie target calculated?
- The calculator uses the Mifflin-St. Jeor equation to estimate your Basal Metabolic Rate (BMR) from your age, sex, height, and weight, multiplies it by an activity factor to get your TDEE, then adjusts for your goal.
- How big should my calorie deficit be for weight loss?
- A moderate deficit of 300–500 calories a day is sustainable and muscle-sparing, aiming for about 0.5–1 lb of loss per week. Very aggressive deficits are hard to maintain and can cost you muscle.
- Is this calorie calculator free?
- Yes — free, no signup, no email. So are the macro calculator, carb calculator, protein calculator, and the Is-It-Keto checker.
Hit your calorie target the easy way
Snap a photo and CarbMeNot logs your calories automatically.
