Free Calorie Calculator —
Find Your Daily Calorie Needs

Enter your details below to calculate your TDEE (Total Daily Energy Expenditure) and see exactly how many calories you need to maintain, lose, or gain weight.

Calculate Your Daily Calories

Weight Loss
calories / day
−500 cal deficit
Maintenance
calories / day
Your TDEE
Weight Gain
calories / day
+500 cal surplus

How your calories were calculated

Basal Metabolic Rate (BMR)
Activity multiplier
TDEE (maintenance)
Formula used Mifflin-St Jeor

Your body system affects how you metabolize food

Gut health, hormonal balance, sleep quality, and stress all determine how efficiently your body uses calories. Take our free 8-question quiz to find out which body system needs your attention most.

Take the Free Health Quiz →

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Frequently Asked Questions

How many calories should I eat per day?

Your daily calorie needs depend on your age, sex, height, weight, and activity level. The average adult needs between 1,600 and 3,000 calories per day. Use the calculator above to find your specific Total Daily Energy Expenditure (TDEE) — your maintenance calorie level. To lose weight, eat 300–500 calories below this. To gain weight, eat 300–500 calories above it.

What is TDEE and how is it calculated?

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day. It is calculated by finding your Basal Metabolic Rate (BMR) — calories your body needs at rest — then multiplying by an activity factor. This calculator uses the Mifflin-St Jeor equation, the most accurate widely-used formula: For men, BMR = (10 × kg) + (6.25 × cm) − (5 × age) + 5. For women, BMR = (10 × kg) + (6.25 × cm) − (5 × age) − 161.

How much of a calorie deficit do I need to lose weight?

A deficit of 500 calories per day typically produces about 1 pound (0.45 kg) of fat loss per week — a safe, sustainable rate. A 250-calorie deficit creates roughly half a pound per week, which is often easier to maintain long-term. Deficits larger than 1,000 calories per day are not recommended without medical supervision, as they can cause muscle loss, nutrient deficiencies, and metabolic adaptation.

Why does my body system affect how I metabolize food?

Calorie numbers are just one part of the picture. Your gut microbiome, hormonal balance, sleep quality, and cortisol levels all affect how efficiently your body processes food. Two people with identical TDEEs can have very different metabolic outcomes depending on gut health, thyroid function, and sleep-driven hormone cycles. Our free health quiz identifies which body system needs support so you can optimize nutrition beyond calories in, calories out.

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