How to use this tool
- Choose units and enter your sex, age, height and weight.
- Pick the activity level that matches a normal week.
- Read your maintenance calories and the targets for losing or gaining weight.
BMR versus TDEE
BMR is what you'd burn lying still all day. Total daily energy expenditure (TDEE) adds digestion, daily movement and exercise, usually 20–90% more. The activity setting above is preset to "little or no exercise"; change it to match your week. For weight goals, base targets on TDEE, not BMR.
What affects BMR
Muscle mass, age, sex, height and weight explain most of the difference between people. BMR falls slightly with age, partly because muscle mass tends to fall. Thyroid disorders can raise or lower it, so unexplained weight change is worth discussing with a doctor.
Frequently asked questions
What is a normal BMR?
Many adult women fall around 1,200–1,500 kcal and men around 1,500–1,900 kcal, depending on size and age.
Is BMR the same as RMR?
Nearly. Resting metabolic rate is measured under looser conditions and is usually slightly higher.
Should I eat my BMR to lose weight?
Not usually. Targets are normally set below TDEE, not BMR. Ask a doctor or dietitian for a personal plan.
Need more detail? See the full Calorie Calculator guide.
Sources and references
- Mifflin MD et al. A new predictive equation for resting energy expenditure. Am J Clin Nutr 1990;51:241–7
- NHS: Understanding calories
- NIH Body Weight Planner