This TDEE calculator to lose weight estimates your Total Daily Energy Expenditure — the number of calories your body burns each day accounting for your basal metabolic rate and physical activity level — and then calculates a target calorie intake to support a sustainable calorie deficit. TDEE is the foundation of evidence-based weight management: to lose weight, calorie intake must consistently fall below TDEE; to maintain weight, intake equals TDEE.
This calculator uses the Mifflin-St Jeor equation, which research published in the Journal of the American Dietetic Association identifies as the most accurate predictive formula for resting metabolic rate in most adults. Understanding your TDEE removes the guesswork from calorie targets and helps you set realistic, achievable weight-loss goals.
Calculate Your TDEE
Enter your details below to estimate your Total Daily Energy Expenditure and a suggested weight-loss calorie target.
What Is TDEE and Why It Matters for Weight Loss
Total Daily Energy Expenditure represents the total number of calories your body uses over a 24-hour period.
It is made up of four components: Basal Metabolic Rate (BMR), which is the energy used at complete rest to maintain basic physiological functions (approximately 60–75% of TDEE for sedentary individuals); the Thermic Effect of Food (TEF), or energy used to digest and metabolize food (roughly 10% of calories consumed); Non-Exercise Activity Thermogenesis (NEAT), covering all movement that is not deliberate exercise, such as walking and fidgeting; and Exercise Activity Thermogenesis (EAT), from structured physical activity.
The Mifflin-St Jeor equation — validated in a landmark 1990 study in the Journal of the American Dietetic Association — estimates BMR from sex, age, height, and weight, which is then multiplied by an activity factor to produce TDEE. The NIH and major dietetic associations recognize TDEE-based calorie targets as the standard starting framework for dietary weight management.
Without knowing your TDEE, it is difficult to set a calorie target that is neither too low (risking muscle loss, nutrient deficiency, and metabolic adaptation) nor too high (insufficient to produce a deficit). For a complementary view of how calorie needs shift with age, see calories by age: what you actually need at every stage.
How to Choose the Right Calorie Deficit
A calorie deficit is the difference between your TDEE and your actual calorie intake. 45 kg) of body fat represents roughly 3,500 calories of stored energy, though the precise relationship varies by individual. As a general guideline, a deficit of 500 calories per day may support loss of approximately one pound per week, while a 250-calorie deficit may support roughly half a pound per week.
NIH weight-management guidelines emphasize that deficits in the range of 500–750 calories below TDEE are generally appropriate for most adults seeking gradual, sustainable weight loss. Very low-calorie diets (below 800 calories per day) should only be undertaken under medical supervision.
Research published in JAMA and The New England Journal of Medicine consistently shows that the composition of the calorie deficit — specifically adequate protein intake — matters significantly for preserving lean muscle mass during weight loss. Use our protein intake calculator to determine the right protein target for your body weight and goals.
6 grams of protein per kilogram of body weight is a commonly cited range supported by the broader nutrition literature. Once you have your calorie target, our macro calculator for women can help you allocate those calories across protein, carbohydrate, and fat.
A moderate deficit supported by strength training tends to produce better body composition outcomes than a severe deficit without exercise; you can also track your progress with the body fat calculator for body composition.
Common TDEE Calculation Mistakes
The most frequent error people make when using a TDEE calculator is overestimating their activity level. The 'moderately active' multiplier assumes dedicated, consistent exercise three to five days per week at genuine moderate intensity — not light daily walks combined with an otherwise sedentary lifestyle. Overestimating activity inflates your TDEE, which can result in maintaining or gaining weight while believing you are in a deficit. A second common mistake is treating TDEE as a fixed number.
' As body weight decreases, BMR decreases proportionally, meaning a calorie target that produced a deficit at 90 kg may produce little or no deficit at 75 kg. Recalculating TDEE every 4–6 weeks as weight changes is therefore important. Tracking food intake accurately — using a food scale rather than estimating portions — is also essential, as studies suggest people underestimate their food intake by an average of 20–40%.
Supporting your deficit with fiber-rich foods that support healthy weight loss can increase satiety and dietary adherence. If you are exploring time-restricted eating as an alternative structure, our intermittent fasting calculator for eating windows can complement your TDEE plan.
Using your TDEE estimate as a starting point and then adjusting based on real weight trends over two to four weeks is a more reliable approach than relying solely on the formula.
Medical Disclaimer: This tool is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment. Results are estimates and should not replace guidance from a qualified healthcare provider. Always consult your doctor before making health decisions.
Frequently asked questions
What is a safe calorie deficit for weight loss?
Most health authorities, including the NIH and major dietetic associations, consider a deficit of 500–750 calories below TDEE to be a reasonable target for gradual weight loss, generally corresponding to approximately 0.5–1 pound of loss per week. More aggressive deficits may be appropriate in certain clinical contexts but carry greater risk of muscle loss, micronutrient inadequacy, and metabolic adaptation. Harvard Health and Mayo Clinic both recommend against dropping below 1,200 calories per day for women or 1,500 calories per day for men without medical supervision, regardless of calculated TDEE.
Does TDEE change over time?
Yes. TDEE is not static. As body weight decreases, BMR decreases proportionally because there is less metabolic tissue to maintain. Additionally, research suggests that prolonged calorie restriction can produce adaptive thermogenesis — a reduction in metabolic rate beyond what weight loss alone would predict — as the body attempts to conserve energy. This is one reason weight-loss progress often slows after an initial period even when calorie intake is held constant. Recalculating your TDEE every 4–6 weeks as your weight changes, and occasionally taking diet breaks at maintenance calories, are strategies some research suggests may help mitigate metabolic adaptation.
How accurate is the Mifflin-St Jeor equation?
The Mifflin-St Jeor equation is considered the most accurate widely available formula for estimating resting metabolic rate in non-obese adults, based on a validation study published in the Journal of the American Dietetic Association. On average, it predicts BMR within approximately 10% of measured values for most people. However, individual variation is significant — factors such as body composition (muscle mass vs. fat mass), thyroid function, medication use, and genetics all influence actual metabolic rate in ways the formula cannot capture. Treat the TDEE output as an informed starting estimate and adjust your calorie target up or down based on your actual weight trend over two to four weeks.
Should I eat back calories burned during exercise?
This depends on how your TDEE was calculated. If your TDEE was estimated using an activity multiplier that already accounts for your exercise level — as this calculator does — then your exercise calories are already incorporated into the TDEE figure, and you should not add them back. If you calculated TDEE at a sedentary level and then exercised, eating back a portion (typically 50–75%) of exercise calories is sometimes recommended to avoid an unintentionally large deficit. Fitness tracking devices and gym equipment consistently overestimate calorie burn during exercise, so caution is warranted when eating back exercise calories based on device readouts.