What is TDEE and why does it matter?

TDEE (Total Daily Energy Expenditure) is the total number of calories you burn per day, including all activities. It's essential for weight management: eat below TDEE to lose weight, above TDEE to gain weight, or at TDEE to maintain. Our TDEE calculator gives you this crucial number.

How is TDEE calculated?

TDEE is calculated by first determining your BMR (Basal Metabolic Rate) using the Mifflin-St Jeor equation, then multiplying by an activity factor (1.2 for sedentary to 1.9 for very active). BMR depends on your weight, height, age, and gender. Our calculator does this automatically.

BMR (Basal Metabolic Rate) is calories burned at complete rest — just for breathing, circulation, and cell production. TDEE includes BMR plus all physical activity. BMR is typically 60-75% of TDEE. For weight management, use TDEE, not BMR.

How many calories should I eat to lose weight?

For healthy weight loss, eat 500 calories below your TDEE (creates a 3,500 calorie weekly deficit = ~0.5kg/week loss). Never go below 1,200 calories (women) or 1,500 calories (men) without medical supervision. Our calculator shows your personalized weight loss calories.

How many calories should I eat to gain muscle?

For muscle gain (bulking), eat 300-500 calories above your TDEE combined with strength training. This slower surplus minimizes fat gain. Our TDEE calculator shows your personalized muscle gain calories target.

What activity level should I choose?

Be honest about your weekly exercise: Sedentary = desk job, no exercise. Light = 1-3 workouts/week. Moderate = 3-5 workouts/week. Active = 6-7 workouts/week. Very Active = intense daily training or physical job. When in doubt, choose lower — you can always adjust.

How accurate is the TDEE calculator?

TDEE calculators are estimates with ~10% margin of error. The Mifflin-St Jeor equation we use is the most accurate available. For best results, use calculated TDEE as a starting point, then adjust based on 2-3 weeks of weight tracking.

Should I eat back exercise calories?

TDEE already accounts for your typical activity level, so you generally don't need to eat back exercise calories separately. If you do an unusual extra workout, you might add 50-75% of those calories back (calorie trackers often overestimate burn).

What is the Mifflin-St Jeor equation?

The Mifflin-St Jeor equation is the most accurate BMR formula, developed in 1990. For men: BMR = (10 × weight in kg) + (6.25 × height in cm) - (5 × age) + 5. For women: same formula but -161 instead of +5. Our calculator uses this formula.

How often should I recalculate my TDEE?

Recalculate TDEE after every 5-10kg of weight change, major changes in activity level, or every 2-3 months. As you lose weight, your TDEE decreases, so you need fewer calories to continue losing. This is why weight loss plateaus happen.

What are maintenance calories?

Maintenance calories equal your TDEE — the amount where you neither gain nor lose weight. Eating at maintenance is useful for 'diet breaks' or maintaining achieved weight. Our calculator shows your maintenance calories automatically.

Why is my TDEE so high/low?

TDEE varies significantly based on: body size (larger bodies burn more), age (metabolism slows with age), gender (men typically burn more), muscle mass (muscle burns more than fat), and activity level. A 6'2" active man may have 2x the TDEE of a 5'2" sedentary woman.

How do I convert calories to kilojoules?

Multiply calories by 4.184 to get kilojoules (1 kcal = 4.184 kJ). Australia and New Zealand use kJ as the primary energy unit on food labels — the recommended adult average reference is 8,700 kJ/day, equivalent to about 2,079 kcal. So a TDEE of 2,500 kcal converts to 10,460 kJ. The UK, US, and Canada label primarily in kcal, though Canadian packaged food carries both kcal and kJ. Our calculator displays kcal by default; just multiply by 4.184 if you need kJ for Australian or NZ food labels.

What does the NHS recommend for daily calories?

The NHS UK reference daily calorie intake is 2,000 kcal for adult women and 2,500 kcal for adult men, used on food labels and traffic-light nutrition guidance. These are population averages assuming moderate activity, not personal targets. Your actual TDEE depends on your age, weight, height, and activity level — a small sedentary woman may maintain on 1,600 kcal while a tall active man may need 3,200 kcal. Use the calculator above for your personalised number; treat the NHS 2,000/2,500 figures as a sanity-check baseline rather than a goal.

Does Health Canada use kcal or kJ for calorie tracking?

Health Canada's Nutrition Facts label uses kcal (Calories) as the primary unit, matching the US format, but the 2019 Canada Food Guide focuses on portion proportions rather than calorie counting. Reference daily intake on Canadian labels is 2,000 kcal for the adult average. Imported and dual-labelled packaged food sold in Canada often shows kJ alongside kcal due to bilingual export-import standards with European markets. For practical TDEE planning in Canada, work in kcal — the same numbers our calculator outputs.

What's the difference between Mifflin-St Jeor and Harris-Benedict?

Both are BMR formulas. Harris-Benedict (1919, revised 1984) was the standard for decades but tends to overestimate BMR by 5-10% for modern populations, partly because body composition shifted toward higher body fat. Mifflin-St Jeor (1990) was developed using a leaner, more recent population sample and is now the American Dietetic Association's recommended formula for adults — it's accurate within ~10% for the majority of healthy individuals. Katch-McArdle is a third option that uses lean body mass instead of total weight; it's the most accurate formula IF you know your body fat percentage from a DEXA scan or bod-pod. Our calculator defaults to Mifflin-St Jeor and switches to Katch-McArdle when you provide body fat %.

What is metabolic adaptation and why does TDEE drop on a long cut?

Metabolic adaptation (also called adaptive thermogenesis) is the body's protective response to a prolonged calorie deficit: BMR drops by 5-15% beyond what weight loss alone predicts, NEAT decreases as you unconsciously fidget and walk less, and exercise feels harder so workouts burn fewer calories. After 12-16 weeks of dieting, a person who started at TDEE 2,500 may now maintain at 2,200 — even at the same weight. The fix isn't pushing the deficit lower; it's a planned diet break of 1-2 weeks at maintenance calories to restore hormonal markers (leptin, thyroid hormones) before resuming the cut. This is why coaches recommend cutting in 8-12 week blocks separated by maintenance phases.

Can I do body recomposition without a calorie deficit or surplus?

Yes — body recomposition (losing fat while gaining muscle simultaneously) is possible at maintenance calories or a very small deficit, but only under specific conditions: you're new to lifting (first 12-18 months), you're returning after a long break (muscle memory effect), you're significantly overweight (high body fat fuels muscle synthesis), or you have very high protein intake (1.6-2.2 g per kg bodyweight). Outside these scenarios, recomp is slow and most lifters progress faster by alternating dedicated cutting and bulking phases. If you want to try recomp, eat at TDEE, hit protein targets, train hard with progressive overload, and judge progress by photos and tape measurements — the scale will barely move.

health_and_safety

TDEE Calculator

calculators.im ↗

Gender

Unit System

Age

years

15 100

Weight

30 kg 200 kg

Height

100 cm 250 cm

Activity Level

Fitness Goal

local_fire_department Daily Calories (TDEE)

2,530 cal/day

Total Daily Energy Expenditure - calories burned per day

bed BMR

1,632

Resting metabolism

flag Target

2,530

Maintain weight

Calorie Breakdown

BMR 65%

Activity 35%

Calorie Goals

trending_down Lose weight

2,030 cal

trending_flat Maintain weight

2,530 cal

trending_up Gain muscle

3,030 cal

restaurant Protein Recommendation

112-140g /day

Based on 1.6-2.0g per kg body weight

info

TDEE is an estimate

Track your weight for 2-3 weeks and adjust calories based on actual results. ±200 cal variation is normal.

Input Values

Age

Gender

Male

Female

Weight

Weight Unit

lbs

Height

Height Unit

inches

Activity Level

expand_more

lightbulb Tips

•TDEE = BMR × Activity Multiplier
•-500 cal/day = ~0.5kg/week loss
•Be honest about activity level
•Recalculate after 5-10kg change

fitness_center Activity Multipliers

Sedentary ×1.2

Light (1-3 days) ×1.375

Moderate (3-5 days) ×1.55

Active (6-7 days) ×1.725

Very Active ×1.9