Which calorie estimate is shown?

The result is predicted resting energy expenditure in kcal/day from the simplified sex-specific Mifflin equations.

Does it calculate maintenance calories or a weight-change target?

No. It does not apply an activity multiplier or present maintenance, deficit, gain, or intake targets.

Can I enter imperial units?

Yes. Pounds are converted to kilograms and inches to centimeters before the same equation is evaluated.

Resting Energy Expenditure Calculator

Supported calculation

This page estimates predicted resting energy expenditure (REE) only. Enter sex, age, height, and weight, choosing metric or imperial units. The starting values are male, age 30, 178 cm, and 75 kg; the stored imperial starting fields are 70 in and 165 lb. Age must be 14–100, and the active height and weight must be positive.

For male inputs:

$\text{predicted REE} = 10 \times \text{weight kg} + 6.25 \times \text{height cm} - 5 \times \text{age years} + 5$

For female inputs:

$\text{predicted REE} = 10 \times \text{weight kg} + 6.25 \times \text{height cm} - 5 \times \text{age years} - 161$

Imperial inputs are converted with weight kg = weight lb × 0.453592 and height cm = height in × 2.54 before evaluation. The calculator retains only predicted REE. It does not infer activity, TDEE, maintenance, weight change, or an intake prescription.

Worked example

For a 30-year-old male at 170 cm and 70 kg:

$10(70)+6.25(170)-5(30)+5=1617.5\text{ kcal/day}$

The shown result is 1,618 kcal/day. With the same age, height, and weight but the female equation:

$10(70)+6.25(170)-5(30)-161=1451.5\text{ kcal/day}$

The shown result is 1,452 kcal/day. The difference comes only from the selected equation constant. Presentation rounding should not be interpreted as measurement-level precision.

Before using the number

Confirm that height and weight belong to the selected unit system.
Treat the output as resting expenditure, not total daily energy use.
Do not add an activity factor unless the next task explicitly calls for one.
If you want to explore a selected subtraction from an activity-adjusted estimate, use the separate calorie-deficit scenario calculator and read its limits first.

Scope and limitations

The cited study derived a predictive equation from 498 healthy subjects, 247 female and 251 male, ages 19–78, including normal-weight and obese participants. The wider entry bounds do not expand that evidence population. REE can differ from a prediction, and this output is not diagnosis or individualized nutrition advice.

Source

Mifflin et al., A new predictive equation for resting energy expenditure in healthy individuals, American Journal of Clinical Nutrition 1990;51(2):241–247, PMID 2305711. Equation and study population are taken from the PubMed abstract passage beginning “A predictive equation…” through “Simplification of this formula…” (accessed July 10, 2026).