Calorie Calculator

How it works

How are daily calorie needs calculated?

The calculator separates resting energy, everyday activity and your chosen goal.

01

Estimate BMR

The Mifflin–St Jeor equation uses age, sex, height and weight to estimate energy used at rest.

02

Estimate TDEE

BMR is multiplied by an activity factor to estimate total daily energy expenditure — the starting point for maintenance calories.

03

Apply your goal

Weight loss uses a 10–20% deficit, muscle gain a smaller 5–15% surplus, and maintenance uses TDEE.

How to use your calorie result

Calories for weight loss

A moderate calorie deficit is usually easier to sustain than an abrupt cut. Use a seven-day weight average and adjust by around 100–150 kcal only if the trend has not changed after 2–3 weeks.

Maintenance calories

TDEE is a useful starting estimate, but actual maintenance varies with movement, body composition and metabolism. A stable multi-week weight trend is the best practical check.

Calories for muscle gain

The muscle-building setting uses a 5–15% surplus. Combine it with progressive resistance training and increase calories gradually if average body weight remains unchanged.

How macros are estimated

In muscle-gain mode, protein is set at 1.8 g/kg, fat at about 25% of calories and the remainder to carbohydrate. Other goals use a practical percentage split.

Real-world check

Why should you calibrate the estimate?

No online calorie calculator measures your metabolism directly. Follow the estimate consistently for 2–3 weeks, weigh under similar conditions and compare weekly averages. Adjust by roughly 100–150 kcal if the trend does not match your goal.

Choose activity from your whole day, not just workouts. Sleep, stress, hydration and menstrual-cycle changes can also move scale weight temporarily without reflecting fat or muscle change.

Calorie calculator FAQ

Clear answers about calories, BMR, TDEE, deficits, activity and muscle gain.

How many calories do I need per day?

Your needs depend on age, sex, height, weight and activity. The calculator estimates BMR first, then multiplies it by an activity factor to estimate TDEE.

What is the difference between BMR and TDEE?

BMR is the energy your body uses at rest. TDEE estimates your whole day, including routine movement and exercise.

How many calories should I eat to lose weight?

Choose a 10%, 15% or 20% deficit from estimated TDEE. Start moderately and assess the seven-day weight trend after 2–3 weeks.

How many calories support muscle gain?

Muscle-gain mode adds 5%, 10% or 15% to TDEE and estimates protein from body weight. Pair the surplus with progressive resistance training.

Is this calorie calculator accurate?

It is a useful starting estimate, not a direct metabolic measurement. Calibrate it using consistent intake and multi-week average body weight.

Which activity level should I choose?

Consider your whole day and week, not workouts alone. A desk job with a few weekly sessions often fits light or moderate activity better than very active.

Can I use it during pregnancy or breastfeeding?

No. Energy and nutrient needs are different during pregnancy and breastfeeding, so ask a doctor or registered dietitian for individual guidance.

Method and sources

Resting needs use the Mifflin–St Jeor equation study. Protein and surplus ranges draw on a sports-nutrition review; while the uncertainty around the ideal surplus is discussed in this hypertrophy review.

Macro starting point

What to do next

How are daily calorie needs calculated?

Estimate BMR

Estimate TDEE

Apply your goal

How to use your calorie result

Calories for weight loss

Maintenance calories

Calories for muscle gain

How macros are estimated

Why should you calibrate the estimate?

Calorie calculator FAQ

Method and sources

Macro starting point

What to do next

How are daily calorie needs calculated?

Estimate BMR

Estimate TDEE

Apply your goal

How to use your calorie result

Calories for weight loss

Maintenance calories

Calories for muscle gain

How macros are estimated

Why should you calibrate the estimate?

Calorie calculator FAQ

Method and sources

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