Basal Metabolic Rate (BMR)
Calories your body burns at complete rest — your metabolic floor.
What BMR tells you
Your Basal Metabolic Rate is the number of calories your body burns just to keep you alive at rest — breathing, circulating blood, maintaining temperature. It typically accounts for 60–70% of the calories you burn each day and is the foundation every calorie and TDEE target is built on.
This calculator offers both the Mifflin–St Jeor equation (recommended for most people) and the revised Harris–Benedict equation, then shows your estimated daily calories across common activity levels. To turn this into a full target, continue to the TDEE calculator.
Frequently asked questions
What is the difference between BMR and TDEE?
BMR is the calories you burn at complete rest. TDEE (Total Daily Energy Expenditure) is your BMR multiplied by an activity factor, so it includes movement and exercise. TDEE is the number you actually eat around.
Which BMR formula should I use?
Mifflin-St Jeor is recommended — it is the most accurate for the general population. The revised Harris-Benedict equation is offered as an alternative and gives similar results.
Should I eat below my BMR?
Generally no. Eating consistently below your BMR is rarely necessary and can be hard to sustain. Fat loss is better driven by a moderate deficit from your TDEE, not by undercutting your resting needs.