BMR is the calories your body burns at complete rest just to stay alive. TDEE is your BMR plus everything else you do in a day — walking, working, exercising, even digesting food. For a typical adult, TDEE runs 20–90% higher than BMR. The rule that matters: always set your calorie target from TDEE, never from BMR alone. Eating at your BMR while living a normal active life is an accidental crash diet. This guide shows you exactly how each number is calculated, with a worked example, so you know which one to use for weight loss, maintenance, or muscle gain.
Our BMR calculator gives you your resting burn and your TDEE side by side, using your age, weight, height, and activity level.
Calculate My BMR and TDEEBMR stands for basal metabolic rate: the number of calories your body burns in 24 hours at complete rest, in a neutral-temperature room, after a full night's sleep and a 12-hour fast. It covers the non-negotiable costs of being alive — your heart beating, lungs breathing, brain thinking, liver filtering, kidneys working, and cells repairing themselves.
For most people BMR is the single largest chunk of daily energy burn: roughly 60–70% of everything you burn in a day. It is also the floor of your calorie needs. Except for short, medically supervised diets, nobody should eat below their BMR for any length of time — doing so means your intake does not even cover basic organ function, let alone movement.
BMR is estimated with formulas that use your weight, height, age, and sex. The most accurate for the general population is Mifflin-St Jeor:
A close cousin you may see is RMR (resting metabolic rate), measured under less strict conditions. RMR typically comes out about 10% higher than BMR, and the two terms are often used interchangeably in everyday fitness advice. For setting calorie targets, the small difference rarely matters.
TDEE stands for total daily energy expenditure: every calorie you burn in a full day of real life. It is your BMR multiplied by an activity factor that accounts for your job, your daily movement, and your workouts:
| Activity level | Multiplier | What it looks like |
|---|---|---|
| Sedentary | BMR × 1.2 | Desk job, little or no exercise |
| Lightly active | BMR × 1.375 | Light exercise or sports 1–3 days/week |
| Moderately active | BMR × 1.55 | Moderate exercise 3–5 days/week |
| Very active | BMR × 1.725 | Hard exercise 6–7 days/week |
| Extremely active | BMR × 1.9 | Physical job plus daily hard training |
TDEE is also, by definition, your maintenance calories — the intake at which your weight stays stable. Eat below it and you lose weight; eat above it and you gain. That is why our full guide on how to calculate TDEE treats it as the anchor number for every calorie goal, and why the TDEE calculator and the maintenance calculator return the same figure.
| BMR | TDEE | |
|---|---|---|
| What it measures | Calories burned at complete rest | Calories burned across your whole real day |
| Includes activity? | No | Yes — job, movement, exercise, digestion |
| Typical share of daily burn | 60–70% of TDEE | 100% — it is the total |
| Example (man, 30, 185 lbs) | ≈ 1,820 calories/day | ≈ 2,820 calories/day (moderately active) |
| Use it for | A floor — rarely eat below this for long | Setting calorie targets for any goal |
Take a 30-year-old man who weighs 185 lbs (84 kg) and stands 5 ft 11 in (180 cm) — the same example we use in our TDEE guide, so you can compare the two articles directly.
Step 1 — BMR (Mifflin-St Jeor, men):
BMR = 10 × 84 + 6.25 × 180 − 5 × 30 + 5 = 840 + 1,125 − 150 + 5 = ≈ 1,820 calories/day. That is what he burns if he stays in bed all day.
Step 2 — TDEE: he has an office job but trains four times a week, so he is moderately active:
TDEE = 1,820 × 1.55 = ≈ 2,820 calories/day.
The gap between the two numbers is a full 1,000 calories a day — an entire meal and then some. And the gap grows with activity: if he were very active (× 1.725), his TDEE would be about 3,140, and eating at his BMR of 1,820 would put him in a 1,320-calorie daily deficit — the kind of aggressive cut that costs muscle, energy, and training performance within weeks.
This is the most common beginner mistake in all of calorie counting, and it usually happens innocently: someone calculates their BMR, mistakes it for their maintenance calories, and eats exactly that amount expecting slow, sensible weight loss. What they actually get depends on their activity:
The fix is simple: find your TDEE first, then subtract a moderate 300–500 calories for weight loss. Our step-by-step guide to how to calculate a calorie deficit walks through that process, or you can let the calorie deficit calculator build the target and timeline for you.
| Goal | Start from | Daily target |
|---|---|---|
| Lose fat | TDEE | TDEE − 300 to 500 calories |
| Maintain weight | TDEE | TDEE itself — your maintenance calories |
| Build muscle | TDEE | TDEE + 200 to 300 calories, with resistance training |
| Sanity-check a diet plan | BMR | Your target should stay at or above BMR for all but very short diets |
Notice the pattern: TDEE is the working number for every goal; BMR is the guardrail. You use TDEE to aim, and BMR to make sure the aim is not dangerously low. If you want your maintenance figure specifically, the maintenance calorie calculator returns your TDEE framed exactly that way.
One last point: both numbers move as you do. Lose or gain about 10 lbs (4.5 kg) and your BMR and TDEE both shift — which is why a calorie target that worked in January can stall by spring. Recalculate every 4–6 weeks, or whenever your weight changes meaningfully, and browse our body and nutrition calculators for the rest of the toolkit.
BMR is your floor, TDEE is your target. Get both from your own stats in under a minute.
Calculate My BMRWritten by the Live Fitness Check editorial team · Reviewed against our calculator methodology · Last updated October 2026
Disclaimer: This guide is for educational purposes only and is not medical advice. Calorie needs vary by individual; consult your doctor or a registered dietitian before starting a weight-loss plan, especially if you are pregnant, nursing, managing a medical condition, or have a history of disordered eating.
