Your TDEE — Total Daily Energy Expenditure — is the number of calories you burn in a typical day. It is the single most useful number in any diet, cut, or bulk plan: eat below it and you lose weight, eat at it and you maintain, eat above it and you gain. This TDEE calculator builds your result in two transparent steps. First it estimates your BMR (Basal Metabolic Rate) with the Mifflin-St Jeor equation, which nutrition researchers consider the most accurate general-purpose resting-energy formula. Then it multiplies that resting figure by an activity factor that matches how much you actually move each day.
Move the inputs and the result updates instantly. You will also see two practical targets underneath: a modest 500 kcal/day deficit for steady weight loss, and a 500 kcal/day surplus for lean weight gain.
How to Use
- Pick your Sex. The Mifflin-St Jeor equation uses a small sex-specific constant, so this matters even though your other numbers are identical.
- Enter your Age in completed years. Resting metabolism drifts down roughly 1–2% per decade after adulthood.
- Type your Height in centimeters. If you measure in inches, multiply by 2.54 first.
- Enter your Weight in kilograms. Divide pounds by 2.205 to convert.
- Choose your Activity Level honestly. Most people underestimate this step — if you sit at a desk and walk only occasionally, you are sedentary, not "moderately active."
- Read the result card. The highlighted TDEE (kcal/day) is your maintenance number: the calories you would need to eat to hold your weight steady.
The card also breaks out your underlying BMR, the kilojoule equivalent, your weekly total burn, and the cut/gain targets derived from your maintenance figure.
The TDEE Formula
Step one computes your resting metabolism with the Mifflin-St Jeor equation (Mifflin et al., 1990):
- Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
- Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Step two scales that resting number upward to account for walking, lifting, sports, fidgeting, and even digesting food — collectively called TEF, NEAT, and EAT. The multipliers in this calculator are the widely adopted standard activity factors:
| Activity level | Description | Factor |
|---|---|---|
| Sedentary | Desk job, little or no planned exercise | 1.2 |
| Lightly active | Light exercise or sports 1–3 days/week | 1.375 |
| Moderately active | Moderate exercise 3–5 days/week | 1.55 |
| Very active | Hard exercise 6–7 days/week | 1.725 |
| Extra active | Very hard exercise plus a physically demanding job | 1.9 |
TDEE = BMR × activity factor.
Worked example: a 30-year-old man who is 175 cm tall and weighs 70 kg has a BMR of 700 + 1093.75 − 150 + 5 = 1648.75 kcal/day. If he trains moderately 3–5 days per week we apply the 1.55 factor, giving a TDEE of 1648.75 × 1.55 = 2555.56 kcal/day. To lose weight he would eat around 2055 kcal/day; to gain he would eat around 3055 kcal/day.
Why Activity Factor Is Where Most People Go Wrong
The difference between sedentary (1.2) and very active (1.725) is roughly a 44% gap in calories. On a 1650 kcal BMR that is about 870 extra calories a day — almost the difference between cutting and bulking on the same body. Researchers consistently find that self-reported activity is optimistic: people who label themselves "moderately active" often burn closer to the lightly-active number. If your weight on the scale is not moving after two weeks at the calculated intake, drop one activity tier before you change anything else.
A common rule of thumb is that a sustained deficit of about 500 kcal/day produces roughly 0.45 kg (1 lb) of fat loss per week, because 1 lb of body fat stores around 3500 kcal. This is a planning estimate, not a guarantee — real results depend on water retention, hormones, sleep, and how much of the weight lost is lean mass. For safety, most coaches do not recommend dropping below about 1500 kcal/day for men or 1200 kcal/day for women without supervision.
Examples
Example 1 — Maintenance for an office worker. A 30-year-old woman, 163 cm, 55 kg, sedentary. Her BMR works out to 1282.75 kcal, and with the 1.2 sedentary factor her TDEE is about 1539 kcal/day. Eating at that level holds her weight steady; a 500 kcal cut lands near 1039 kcal, which is close to the advised female floor, so she may prefer a smaller deficit and more daily walking instead.
Example 2 — Active recreational lifter. A 40-year-old man, 180 cm, 85 kg, who lifts hard 6 days a week (very active, factor 1.725). His BMR is 1780 kcal and his TDEE is 3070.5 kcal/day. A 500 kcal surplus puts his lean-bulk target near 3570 kcal, while a cut to roughly 2570 kcal supports gradual fat loss while keeping his strength sessions fed.
Example 3 — Re-checking after a stall. Someone eats what they think is a cut, sees no movement for three weeks, and re-runs this tool. They had selected "very active" but actually train twice a week and sit at a desk — the honest tier is lightly active (1.375). Their real TDEE drops by several hundred kcal, which explains why their "cut" was actually maintenance.
FAQ
What does TDEE stand for?
TDEE stands for Total Daily Energy Expenditure — the total number of calories you burn in one day, including your resting metabolism, daily movement, exercise, and the energy used to digest food. It is your true maintenance calorie target.
How is TDEE different from BMR?
BMR is the energy you would burn lying perfectly still all day: just breathing, brain function, heart beat, and temperature control. TDEE multiplies that resting figure by an activity factor to add walking, work, workouts, and chores. BMR is the floor; TDEE is your real-world daily burn.
Which activity level should I choose?
Be conservative. If you have a desk job and exercise 1–3 days a week, pick "lightly active" (1.375). Only choose "very active" (1.725) if you train hard most days of the week. Overestimating activity is the most common reason a calculated TDEE fails to match the scale.
How accurate is this calculator?
The Mifflin-St Jeor equation predicts average resting metabolism within about ±10% for most adults, and multiplying by an activity factor adds another rough band. Treat the result as a planning estimate, not a lab measurement. Weigh yourself consistently for 2–3 weeks and adjust your food intake up or down by 100–200 kcal until the scale moves the way you want.
How many calories should I eat to lose weight?
Start at your calculated TDEE and subtract about 500 kcal per day for roughly 0.45 kg (1 lb) of loss per week. Avoid dropping below roughly 1500 kcal/day for men or 1200 kcal/day for women without a clinician's guidance, since very low intakes risk losing muscle and missing nutrients.
How many calories should I eat to gain weight?
Add about 250–500 kcal per day above your TDEE and pair the surplus with resistance training. A larger surplus builds fat faster than muscle; the modest surplus shown as the "+500 kcal" target is tuned for gradual, mostly lean gain.
Does TDEE change as I lose or gain weight?
Yes. Your TDEE is tied to your body weight, so every few kg lost lowers your maintenance by roughly 10–20 kcal per kg per day. Re-run this calculator whenever your weight changes by about 5 kg, or whenever the scale stalls for two weeks.
Disclaimer
This TDEE calculator is provided for informational purposes only and is not medical advice. Estimates are based on the Mifflin-St Jeor equation and standard activity multipliers, which are population averages and may not reflect your individual metabolism, medical conditions, medications, or body composition. Do not use these numbers to diagnose, treat, or manage any health condition. Before making major changes to your diet, starting an aggressive cut or bulk, or if you have a history of disordered eating, consult a qualified doctor or registered dietitian.