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BMR Calculator

Estimate resting energy expenditure with the Mifflin–St Jeor equation.

Understand the limitations belowMeasurements stay on this device
Personal estimate
Personal estimate

Read the supported population and limitations before using the result.

See the method

Enter your measurements

Runs on your device

Your estimate

Your result

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Use the Calculate button to see your result.

An estimate, not a diagnosis.

How to use this tool

  1. Enter weight, height, age, sex used in the equation.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

Input reference and sample values

Use the units and choices shown for each field. Sample values are provided for practice, not as recommendations.

InputFormat and unitsSample
WeightNumeric value. Unit: kg. Minimum: 1. Maximum: 700.70
HeightNumeric value. Unit: cm. Minimum: 1. Maximum: 300.175
AgeNumeric value. Unit: years. Minimum: 20. Maximum: 100.30
Sex used in the equationChoose Male coefficient / Female coefficient.Male coefficient

Result for these sample inputs

1648.75 kcal/day
Equation
Mifflin–St Jeor
Activity calories
Not included

An estimate of resting needs, not a daily calorie target or a recommendation for weight loss.

Select Try the example in the form to load these values and calculate them again. This replaces the current form inputs. Compare the result with the method and worked explanation below.

The method, explained

Estimated resting kcal/day = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + coefficient. The original equation uses +5 for men and −161 for women.

A WORKED EXAMPLE

For a 30-year-old using the male coefficient at 70 kg and 175 cm, the estimate is 1,648.75 kcal/day.

What to keep in mind

This equation estimates resting expenditure rather than measuring metabolism. It excludes activity and is not a calorie intake target. Not intended for pregnancy, children, or clinical nutrition decisions.

Reference: Original Mifflin–St Jeor study

Common questions

Does this include exercise?

No. Resting energy and total daily energy expenditure are different. Activity requires additional energy.

Why does the form ask for a sex coefficient?

The published equation uses two sex-specific coefficients. It may not represent every individual accurately; clinical assessment can offer a more suitable estimate.

Methodology maintained by ClarityKit. How these tools are built and checked.