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TDEE calculator

Enter your sex, age, weight and height, then choose an activity level. You get resting energy from the Mifflin-St Jeor equation and an estimate of the calories you burn in a day.

Updated

Sex
years

– kcal a day

Resting energy (Mifflin-St Jeor)
–
Activity level used
–
Same in kilojoules
–

Fill in age, weight and height to see the estimate.

Calculated in your browser. Nothing is sent or saved.

An estimate for a typical person with your numbers; measured energy use can differ by several hundred kcal. Not medical or dietary advice.

The formula this calculator uses

  1. Units

    lb × 0.45359237 = kg · ft × 30.48 + in × 2.54 = cm.

  2. Resting energy (REE)

    men: 10 × kg + 6.25 × cm − 5 × age + 5 · women: 10 × kg + 6.25 × cm − 5 × age − 161 [1]. Shown rounded to a whole kcal.

  3. Daily total

    TDEE = REE × PAL, rounded to a whole kcal · kJ = TDEE × 4.184, rounded.

Worked examples

Each row was entered into this calculator and the result copied as shown.

TDEE calculator results for three sample entries
EntryResting energyPALTDEEkJ
Male · 40 · 80 kg · 180 cm1,730 kcal1.552,682 kcal11,219 kJ
Female · 35 · 70 kg · 165 cm1,395 kcal1.41,953 kcal8,173 kJ
Female · 60 · 65 kg · 160 cm1,189 kcal1.72,021 kcal8,457 kJ

Choosing an activity level

FAO/WHO/UNU lifestyle categories by physical activity level (PAL)
LifestylePAL range [2]Values offered here
Sedentary or light activity1.40 to 1.691.40 · 1.55
Active or moderately active1.70 to 1.991.70 · 1.85
Vigorous or vigorously active2.00 to 2.402.00 · 2.20

FAO/WHO notes that PAL values above 2.40 are hard to keep up over long periods [2].

What this calculator does not do

  • It does not give a calorie target, a deficit or a diet.
  • It does not measure your metabolism; it estimates it from four numbers.
  • It does not account for body composition, illness, pregnancy or medications.
  • It does not predict weight change.

About this estimate and your privacy

In the study that produced it, the Mifflin-St Jeor equation explained about 71% of the variation in measured resting energy (R² = 0.71) [1]. Individual results can still differ by a meaningful amount.

Everything is worked out by a script inside this page. The script makes no network requests, the page’s security policy (Content-Security-Policy with default-src none and no connect-src) would block them anyway, and nothing you type is stored, not even in your browser’s storage. Reload the page and the fields are empty again.

Next to each source below is what it supports on this page.

Questions

What is the difference between resting energy and TDEE?

Resting energy is what your body uses at complete rest. TDEE adds everything else in a day: moving, working, exercising and digesting food. PAL is the ratio between the two [2].

Why Mifflin-St Jeor?

It was derived in 1990 from measured resting energy in 498 healthy adults of normal weight and with obesity, and in that study the older Harris-Benedict equations overestimated measured values by about 5% [1].

Which activity level should I pick?

FAO/WHO describes three bands: sedentary or light (1.40–1.69), active or moderately active (1.70–1.99) and vigorous (2.00–2.40) [2]. The list offers the lower end and the middle of each band; choose "My own value" for anything else.

Should I eat less than my TDEE to lose weight?

This page only estimates energy use. How much to eat, especially alongside a GLP-1 medication, is a decision for you and your clinician or dietitian.

Does my TDEE change as I lose weight?

Yes. Weight is one of the terms in the equation [1], so each kilogram less lowers resting energy by 10 kcal in this formula. Re-enter your numbers after a change.

What if a GLP-1 medication makes me eat much less?

The 2025 joint advisory lists nutrient deficiencies due to calorie reduction among the challenges of GLP-1 therapy [3]. Talk to your care team about what eating much less means for you; this calculator only estimates energy use.

Does it work for every age?

The equation was derived in adults aged 19 to 78 [1]. The calculator still works outside that range but shows a note.

How accurate is it?

In the original study the equation explained about 71% of the variation in measured resting energy [1]. That is useful for a typical estimate and not precise for one person.

Why show kilojoules?

Food labels in many countries use kJ. The calculator multiplies kcal by 4.184.

Sources

Sources checked on

  1. Mifflin MD, St Jeor ST et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990;51(2):241-7 Supports: the simplified REE equations for men and women; 498 participants aged 19 to 78; R² 0.71; Harris-Benedict overestimating by 5%.
  2. FAO/WHO/UNU. Human energy requirements (2004), Table 5.3: lifestyles by physical activity level (PAL) Supports: the three PAL bands; values above 2.40 hard to maintain.
  3. Mozaffarian D et al. Nutritional priorities to support GLP-1 therapy for obesity: a joint Advisory from ACLM, ASN, OMA and TOS. Am J Clin Nutr. 2025;122:344-367 Supports: nutrient deficiencies due to calorie reduction as a challenge of GLP-1 therapy.

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