TDEE calculator: how many calories you burn a day
Enter your sex, age, weight, height and activity level to see your maintenance calories and targets for losing or gaining weight.
Based on the Mifflin-St Jeor equation (1990) and the 2013 AHA/ACC/TOS obesity guidelineLast reviewed: October 9, 2026
The short answer
Your TDEE is your basal metabolic rate times an activity factor. BMR comes from the Mifflin-St Jeor equation using weight, height, age and sex; the factor runs from 1.2 for sedentary to 1.9 for extra active. To lose weight, eat 500 to 750 calories below TDEE, but not under 1,200 a day for women or 1,500 for men.
How it is calculated
BMR (men) = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
BMR (women) = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
1 lb = 0.4536 kg, 1 in = 2.54 cm. The calculator converts for you.
TDEE = BMR × activity factor (1.2, 1.375, 1.55, 1.725 or 1.9)
Weight-loss target = TDEE − 500 or − 750, never below 1,200 (women) or 1,500 (men).
Worked example
Mike is 40, weighs 200 lb, stands 5 ft 9 in and works out moderately 4 days a week.
- Convert: 200 lb = 90.7 kg, 5 ft 9 in = 175.3 cm
- BMR: 10 × 90.7 + 6.25 × 175.3 − 5 × 40 + 5 = 1,808 calories
- Moderately active: 1,808 × 1.55 = 2,802 calories to maintain
- Weight loss: 2,802 − 500 = 2,302; faster loss: − 750 = 2,052
Mike burns about 2,802 calories a day and can aim for about 2,302 to lose weight.
Quick reference table
| Activity level | Man, 190 lb, 5 ft 9 in | Woman, 160 lb, 5 ft 4 in |
|---|---|---|
| Sedentary (× 1.2) | 2,175 | 1,717 |
| Lightly active (× 1.375) | 2,492 | 1,967 |
| Moderately active (× 1.55) | 2,809 | 2,218 |
| Very active (× 1.725) | 3,126 | 2,468 |
| Extra active (× 1.9) | 3,443 | 2,718 |
Special cases and common mistakes
- A floor for weight loss. The 2013 AHA/ACC/TOS guideline prescribes 1,200 to 1,500 calories a day for women and 1,500 to 1,800 for men who are losing weight. This calculator never shows a loss target below the low end of that range and tells you when it raised one.
- Pregnant or breastfeeding? Your needs are different and change by stage. The equation was not built for pregnancy, so ask your OB or a registered dietitian.
- Age range. Mifflin-St Jeor was derived from 498 adults aged 19 to 78. The calculator works from 18 and flags ages outside the study range. It is not meant for children or teens.
- Be honest about activity. The most common mistake is picking a level that is too high. A desk job with a few walks a week is sedentary.
- Mifflin-St Jeor or Harris-Benedict? The Mifflin study found the 1919 Harris-Benedict equations overestimated measured resting energy by about 5%, which is why most dietitians now use Mifflin-St Jeor.
- Treat it as a starting point. Real burn varies from person to person. Track your weight for two to three weeks and adjust.
Frequently asked questions
How many calories should I eat a day to lose weight?
Start from your TDEE and subtract 500 to 750 calories a day, the deficit named in the 2013 AHA/ACC/TOS obesity guideline. Do not go below 1,200 calories a day for women or 1,500 for men without medical supervision.
What is the difference between BMR and TDEE?
BMR is what your body burns at complete rest. TDEE is everything you burn in a day including movement and exercise; it equals BMR times your activity factor.
Which activity level should I pick?
Sedentary if you sit most of the day and rarely exercise, lightly active for light exercise 1 to 3 days a week, moderately active for 3 to 5 days, very active for hard exercise 6 to 7 days, extra active for very hard training plus a physical job.
How many calories do I need to gain weight?
A common rule of thumb is about 500 calories above your TDEE. It is not a fixed medical number, so track your weight and adjust, and see a doctor if weight loss was unintentional.
Can I use this TDEE calculator while breastfeeding?
No. Breastfeeding and pregnancy change energy needs in ways this equation does not cover. Ask your doctor or a registered dietitian.
How accurate is the Mifflin-St Jeor equation?
It predicted measured resting energy well in its 1990 study (R² = 0.71) and beat Harris-Benedict, but any equation is an estimate. Your real numbers can be higher or lower.
Sources
- Mifflin MD, St Jeor ST et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr 1990 (abstract) (Last reviewed: October 9, 2026)
- Texas Health and Human Services, Common Comparative Standards for RDs: Estimating Energy Needs (activity factors), rev. 10/2022 (Last reviewed: October 9, 2026)
- 2013 AHA/ACC/TOS Guideline for the Management of Overweight and Obesity in Adults, Points to Remember (Last reviewed: October 9, 2026)