TDEE calculator
Find out how many calories you burn in a day, and how many you need to eat to maintain, lose or gain weight.
How this calculator works
First it estimates your basal metabolic rate (BMR), the energy your body uses at rest, with the Mifflin-St Jeor equation: 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. A systematic review found it the most reliable of the commonly used equations for both normal-weight and obese adults.
Then it multiplies BMR by an activity factor, from 1.2 for sedentary to 1.9 for very physical lives, to estimate total daily energy expenditure (TDEE).
Every equation is an average. The best way to find your real maintenance level is to eat a consistent amount, log it, and watch your weight trend for a few weeks. That's exactly what PromptlyFit does with you, inside your AI assistant.
Frequently asked questions
What is TDEE?
Total daily energy expenditure is the number of calories you burn in a day: your resting metabolism (BMR) plus digestion and all movement, from walking around to workouts. Eating at your TDEE keeps your weight roughly stable.
How accurate is this calculator?
The Mifflin-St Jeor equation is the most reliable of the common BMR equations, but it is still an estimate: individuals can differ from it by 10% or more. Treat the result as a starting point, track your weight for two to three weeks, and adjust.
Which activity level should I pick?
Most people overestimate. If you have a desk job and work out three or four times a week, "Moderately active" is usually the highest you should choose; if unsure, pick one level lower.
How many calories should I eat to lose weight?
A deficit of about 500 calories a day below your TDEE leads to roughly 0.5 kg (1 lb) of loss per week at first. Use the macro calculator to turn that into daily calorie and protein targets.
Sources
- Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990.
- Frankenfield D, et al. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review. J Am Diet Assoc. 2005.
These calculators give estimates for healthy adults and aren't medical advice. If you're pregnant, under 18, or managing a medical condition, talk to a doctor or registered dietitian before changing how you eat.