TDEE Calculator: Your Maintenance Calories

TDEE Calculator: Find Your Maintenance Calories

Your TDEE is the number of calories you burn in a day, and so the number you eat to keep your weight steady. Enter your details for your maintenance calories, the targets for losing fat or gaining muscle, and how three standard formulas compare.

By the FitStack team. Last updated October 18, 2026. Formulas and sources are listed on this page.

How this TDEE calculator works

The calculator estimates your basal metabolic rate (BMR) from your sex, age, height and weight, then multiplies it by an activity factor to get your total daily energy expenditure (TDEE). If you enter your body fat percentage, it uses your lean mass instead.

Mifflin-St Jeor (default)

Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5 Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161

Published by Mifflin, St Jeor and colleagues in 1990 from measurements of 498 adults.¹ A systematic review for the American Dietetic Association (now the Academy of Nutrition and Dietetics) found it the most reliable of the common equations.⁴

Katch-McArdle (when you know your body fat)

BMR = 370 + 21.6 × lean body mass (kg) Lean body mass = weight × (1 − body fat % / 100)

Lean tissue burns far more energy at rest than fat, so working from lean mass helps people who are unusually muscular or carry more body fat than average. It is only as good as the body fat number you give it; a tape or smart-scale estimate can be several points off. The Navy body fat calculator gives you a consistent estimate to use here.

Revised Harris-Benedict (for comparison)

Men: BMR = 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age Women: BMR = 447.593 + 9.247 × weight + 3.098 × height − 4.330 × age

The 1984 revision by Roza and Shizgal of the original 1919 equation.³ It tends to come out slightly higher than Mifflin-St Jeor, which is why we show it next to your result rather than use it.

Activity multipliers

The multiplier converts resting energy into a full day. These are the standard factors used with BMR equations. The FAO/WHO/UNU expert report describes the same idea as the physical activity level (PAL), from about 1.4 for sedentary lifestyles to 2.4 for very heavy work.⁵

Level	Multiplier	Typical week
Sedentary	1.2	Desk job, little or no exercise, under about 5,000 steps a day
Lightly active	1.375	Exercise 1 to 3 days a week, or a job with some walking
Moderately active	1.55	Exercise 3 to 5 days a week, or about 10,000 steps a day
Very active	1.725	Hard exercise 6 to 7 days a week, or a physical job
Extremely active	1.9	Twice-daily training or heavy manual labor plus exercise

Most people overestimate their activity. Three one-hour gym sessions a week is closer to "lightly active" than "very active" if you sit for the rest of the day. When in doubt, pick the lower level and let your weigh-ins tell you if you were wrong.

Worked example

A 34-year-old woman, 168 cm (5' 6") and 72 kg (159 lb), who exercises three to four times a week:

BMR = 10 × 72 + 6.25 × 168 − 5 × 34 − 161 = 1,439 kcal TDEE = 1,439 × 1.55 (moderately active) = 2,230 kcal a day Fat loss (−20%) = about 1,780 kcal a day

Why your real TDEE differs from any calculator

Equations describe the average person with your measurements. Two people with identical stats can differ by several hundred calories a day, mostly from differences in daily movement (NEAT).⁷ Energy needs also fall as you lose weight, and food logs are rarely exact.

The reliable way to find your true maintenance is to treat this result as a starting point: eat it consistently for two to three weeks, track your morning weight, and adjust from the trend. That is what FitStack does automatically from your logs. To plan the next step, use the calorie deficit calculator for a fat-loss target or the macro calculator to split your calories into protein, carbs and fat.

Assumptions and limits

Built for adults aged 18 to 80. It does not apply during pregnancy or breastfeeding, or to children and teens.
Medical conditions and some medications (for example thyroid conditions or beta blockers) change energy needs.
The fat-loss and lean-gain rows use ±10 to 20% of maintenance and roughly 7,700 kcal per kg of body weight change, which over-predicts loss over long periods.⁶

Frequently asked questions

What is the difference between TDEE and BMR?

BMR (basal metabolic rate) is the energy your body uses at complete rest: breathing, circulation, keeping organs running. TDEE (total daily energy expenditure) is BMR plus everything else: digesting food, daily movement, steps and exercise. For most people BMR is 60 to 70% of TDEE, and TDEE is the number you eat to maintain your weight.

Which TDEE formula is most accurate?

For most adults, Mifflin-St Jeor. A systematic review by Frankenfield and colleagues (2005) found it predicted resting metabolic rate within 10% of the measured value in more people, lean or with obesity, than the other common equations. If you have a reliable body fat measurement, Katch-McArdle can be closer because it works from lean mass, which drives most of your resting energy use.

Should I eat my TDEE to maintain my weight?

Yes, as a starting point. Eat close to your TDEE for two to three weeks, weigh yourself each morning, and compare weekly averages. If the average holds steady, that intake is your real maintenance. If it drifts up or down, adjust by 100 to 150 calories a day and check again.

How often should I recalculate my TDEE?

Recalculate after every 4 to 5 kg (about 10 lb) of weight change, or when your activity changes for more than a few weeks, such as a new job, a training block or an injury. Better still, let your weigh-ins and food log tell you: if your weight trend stops matching the plan for two to three weeks, your real TDEE has moved.

Do my daily steps (NEAT) matter?

A lot. Non-exercise activity thermogenesis, the energy you burn walking, standing and fidgeting, varies by hundreds of calories a day between people and between days. It often falls without you noticing when you diet. Keeping your step count steady is one of the simplest ways to keep your TDEE from drifting down during a cut.

Why does my real weight change not match the calculator?

Every equation predicts the average person with your stats, and individuals differ by 10% or more. Food logging is also rarely exact, and water weight from salt, carbohydrate and hormonal cycles can hide fat loss for a week or two. Use the calculator for your first target, then let two to three weeks of weigh-ins correct it.