Use this energy estimate as a starting point for planning or comparing intake and activity assumptions when body measurements and activity level are entered consistently.

Age (years)

Age in years.

Height (cm)

Height in centimeters.

Weight (kg)

Weight in kilograms.

Sex

Sex used by the equation.

Estimate daily resting energy expenditure with the Mifflin-St Jeor equation. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Calories per day (kcal/day)

Resting energy expenditure per day.

• BMR and daily-expenditure equations estimate population averages rather than an individual's metabolism. Body composition, age, sex, health, medication, pregnancy, climate, activity measurement, and adaptive changes can shift actual needs.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Track weight, intake, performance, and wellbeing over several weeks and adjust gradually. Seek clinical or dietetic guidance for medical conditions, pregnancy, eating disorders, or major weight changes.

• Total Daily Energy Expenditure

  Scale a basal metabolic rate into daily maintenance calories by activity level.

• BMR Mifflin St Jeor Calculator

  Compute basal metabolic rate with the Mifflin St Jeor equations.

• Kleiber BMR

  Estimate basal metabolic rate across animals with Kleiber's law: BMR = 70 x bodyMass^0.75 kilocalories per day.