Health calculator

Calorie Calculator

Estimate daily calories for maintenance, weight loss, or weight gain using your age, body size, and activity level.

Estimate your daily energy needs

Choose your measurement system, enter your details, and select the goal you want to explore.

Private calculation

Adult estimate: This calculator is designed for adults aged 18 and older. It is not intended for pregnancy, breastfeeding, competitive athletes, or people with conditions that significantly affect metabolism.

Sex used by equation The Mifflin–St Jeor equation uses sex-specific constants. Age years Enter an age from 18 through 100.

Height cm Enter a height between 120 and 230 cm. Weight kg Enter your current weight in kilograms.

Activity level Choose the description closest to your average week. Activity multipliers are broad estimates, not precise measurements.

Goal

Custom daily adjustment Use a negative number for a deficit or positive number for a surplus. kcal

Your daily target — kcal Maintain weight

Your calorie estimate

Enter your details to estimate your daily calories.

Mifflin–St Jeor estimate

Maintenance calories — Estimated daily energy expenditure

Resting energy — Estimated calories at rest

Weekly target — Daily target multiplied by seven

Activity allowance — Difference between maintenance and rest

Estimated maintenance range

Real needs can vary, so use this range as a starting point and adjust from real-world results.

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−10%Estimate+10%

How to use this number

Use the estimate as a starting point, then compare it with changes in body weight, hunger, energy, training, and health over several weeks.

Compare activity levels and goals

See how the same body measurements produce different estimates when activity or goals change.

Maintenance by activity level

Activity level	Daily calories

Targets by goal

Goal	Daily calories

About the Calorie Calculator

This calculator estimates how much food energy an adult may need each day. It first estimates resting energy expenditure and then adjusts that value for activity and the selected weight goal.

How the calculation works

The calculator uses the Mifflin–St Jeor equation, which estimates resting energy expenditure from weight, height, age, and the sex-specific constant selected in the form. The resting estimate is multiplied by a broad activity factor to estimate maintenance calories.

Male equation 10W + 6.25H − 5A + 5

Female equation 10W + 6.25H − 5A − 161

W is weight in kilograms, H is height in centimeters, and A is age in years.

Why your actual calorie needs may differ

Prediction equations estimate averages and can be meaningfully high or low for an individual.
Activity labels cannot perfectly capture exercise, occupation, daily movement, and recovery.
Body composition, medications, illness, sleep, and recent weight change can affect energy expenditure.
Energy needs can change over time as body weight and activity change.

Using the result

Start with the estimate, track your average intake and body-weight trend consistently, and make small adjustments only after enough time has passed to see a pattern. A registered dietitian or qualified healthcare professional can provide individualized guidance.

Privacy

Your age, height, weight, activity level, and goal are processed only inside your browser. Toolslight does not send or store the values you enter here.

Health note: This calculator provides a general educational estimate, not medical or nutrition advice. Seek professional guidance for pregnancy, breastfeeding, eating-disorder concerns, metabolic disease, unexplained weight change, or highly demanding athletic training.