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BMR & Calorie Needs Calculator

Estimate basal metabolic rate and daily calorie needs with Mifflin–St Jeor.

Live estimate

Your inputs

Enter your measurements

Units
Equation profile

Mifflin–St Jeor and activity multipliers provide estimates, not individualized nutrition advice. Energy needs vary.

Estimated maintenance

2,556 kcal/day

Mild weight loss2,306 kcal/day250 kcal below estimate
Maintenance2,556 kcal/day
Mild weight gain2,806 kcal/day250 kcal above estimate
MethodMifflin–St Jeor equation

BMR estimates energy used at rest; activity adjusts it to a daily maintenance estimate.

About this tool

Estimate energy needs at rest and in daily life

Basal metabolic rate estimates the energy the body uses at rest. This calculator applies the Mifflin–St Jeor equation to age, weight, height, and the selected equation profile.

An activity multiplier converts BMR into an estimated daily maintenance level. Both the equation and activity choice are broad estimates; actual energy needs change with body composition, health, training, and daily movement.

How it works

Estimate daily calorie needs

  1. 1Choose profile and units

    Select the equation profile and metric or US measurements.

  2. 2Enter age and size

    Add age, current weight, and height.

  3. 3Select activity

    Choose the closest activity level to estimate maintenance calories.

Common questions

BMR & Calorie Needs FAQ

What is the difference between BMR and maintenance calories?

BMR estimates rest energy; maintenance multiplies BMR by an activity factor to estimate total daily needs.

Which formula is used?

This tool uses the Mifflin–St Jeor predictive equation published in 1990.

Are the calorie targets exact?

No. They are starting estimates and can differ from measured energy expenditure.

References

Sources & references

This tool is informational and is not a substitute for professional medical or financial advice. Its methodology draws on the primary sources below.