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BMI, calorie & wellness calculators
TDEE Calculator
BMR by Mifflin-St Jeor, Harris-Benedict or Katch-McArdle × an activity factor → TDEE, plus goal calories for cut/maintain/bulk. A fitness estimate — the activity factor is the biggest variance. Accurate, instant and free — for United States.
What these mean:
What these mean:
What these mean:
What these mean:
What these mean:
BMR ≈ 1780 kcal/day (Mifflin-St Jeor); TDEE ≈ 2759 kcal/day at your activity level. Goal calories ≈ 2207 kcal/day — cutting 20% (≈ 552 kcal/day deficit). An estimate — don't go below your BMR; general fitness guidance, not medical advice.
BMR
1780 kcal
TDEE
2759 kcal
Goal calories
2207 kcal
Which BMR formula should I use?
The activity multiplier is the biggest variance
Goal rate → timeline
A ≈ 552 kcal/day deficit is roughly ≈ 1.1 lb/week (≈ 3,500 kcal ≈ 1 lb of fat).
Recalculate every ~10 lb — your TDEE drops as you lose weight (less mass to maintain, plus metabolic adaptation), so the same deficit yields a smaller gap over time.
An estimate — not medical or dietary advice
How we calculate this
Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.
BMR via Mifflin-St Jeor / Harris-Benedict / Katch-McArdle; TDEE = BMR × activity. An estimate — general fitness guidance, not medical or dietary advice.
Mifflin-St Jeor 1990 · Harris-Benedict · Katch-McArdle · activity factors 1.2–1.9
Turn these calories into a plan: split them with the Macro Calculator, set your protein target, and track progress with the Weight-Loss Percentage Calculator.
BMR × activity → TDEE, then goal calories
From your sex, age, height and weight this tool estimates your BMR (resting burn), multiplies it by an activity factor for your TDEE (total daily burn), and applies your goal to show goal calories — cut, maintain or bulk. Every figure carries its unit (kcal), and you can switch between three BMR formulas.
BMR + TDEE
resting → total burn
Mifflin = 10·kg + 6.25·cm − 5·age + (♂ +5 / ♀ −161) ; TDEE = BMR × activity
Activity factors: 1.2 sedentary, 1.375 light, 1.55 moderate, 1.725 very active, 1.9 extra active.
Goal calories
cut / maintain / bulk
goal calories = TDEE × (1 + goal%)
Cut −20% for fat loss, maintain at 0%, bulk +10% for muscle gain. Don’t set goal calories below your BMR.
- 1BMR (Mifflin): 10×80 + 6.25×180 − 5×30 + 5 = 800 + 1125 − 150 + 5 = 1,780 kcal.
- 2TDEE + goal: TDEE = 1,780 × 1.55 = 2,759 kcal; cut −20% = 2,759 × 0.8 = 2,207 kcal (≈ 552 kcal/day deficit ≈ 1.1 lb/week). A woman with the same stats has a BMR of 1,614.
Mifflin vs Harris-Benedict vs Katch-McArdle
Most calculators quietly pick one equation. This one lets you compare all three, and tells you which to trust. Mifflin-St Jeor (1990) is the most accurate for most people — the default. The revised Harris-Benedict equation is older and tends to overestimate BMR by 5–15%, especially in sedentary people. Katch-McArdle (370 + 21.6 × lean-kg) can be the most accurate of all — but only if you know your body-fat %, since it works from lean mass and ignores age and sex.
When to pick each one
The activity table (1.2 – 1.9)
TDEE is BMR times an activity factor, and that factor is where most of the uncertainty lives:
| Level | Factor | Roughly |
|---|---|---|
| Sedentary | 1.2 | little or no exercise |
| Lightly active | 1.375 | 1–3 days/week |
| Moderately active | 1.55 | 3–5 days/week |
| Very active | 1.725 | 6–7 days/week |
| Extra active | 1.9 | hard training / physical job |
Most people overestimate their activity. If your weight is not moving as expected after 2–3 weeks, the activity factor — not the formula — is usually the reason. Adjust it before anything else.
Goal calories and the macro hand-off
Goal calories are simply TDEE × (1 + goal%): a cut subtracts a percentage (−20% is a common starting deficit), maintain keeps you at TDEE, and a bulk adds a modest surplus (+10%). Calories tell you how much to eat; macros tell you what those calories are made of. Hand your goal calories to the Macro Calculator to split them into protein, carbs and fat, and set a protein target first.
Don’t cut below your BMR
Your TDEE drops as you lose weight
TDEE is a snapshot, not a constant. As you lose weight you carry less mass to move and maintain, so your BMR falls — and the body also downregulates energy use somewhat (adaptive thermogenesis). The same calorie target therefore produces a smaller and smaller deficit over time, which is why weight loss stalls even when nothing has “gone wrong.” The fix is simple: recalculate your TDEE every ~10 lb (≈ 5 kg) with your new weight, and track the trend with the Weight-Loss Percentage Calculator.
Frequently asked questions
BMR (basal metabolic rate) is the energy your body burns at complete rest just to stay alive — breathing, circulation, cell repair. TDEE (total daily energy expenditure) is BMR multiplied by an activity factor (1.2 to 1.9) to account for movement, exercise and the energy cost of digesting food. TDEE is the number that matters for diet: eat at TDEE to maintain weight, below it to lose, above it to gain. For a 30-year-old man of 80 kg and 180 cm at a moderate activity level, BMR is about 1,780 kcal and TDEE about 2,759 kcal per day.
Mifflin-St Jeor (1990) is the most accurate for most people and is the default here. The revised Harris-Benedict equation is older and tends to overestimate BMR by roughly 5–15%, especially in sedentary people. Katch-McArdle can be the most accurate of all, but only if you know your body-fat percentage — it works from lean body mass (weight × (1 − body-fat%)) and ignores age and sex. If you do not know your body composition, use Mifflin.
The standard factors are 1.2 (sedentary — little or no exercise), 1.375 (lightly active — 1–3 days a week), 1.55 (moderately active — 3–5 days), 1.725 (very active — 6–7 days) and 1.9 (extra active — hard daily training or a physical job). The activity factor is the single biggest source of variance in a TDEE estimate, and most people overestimate how active they are. Pick honestly, then refine against real weight change over 2–3 weeks.
To lose fat, eat below your TDEE. A common starting deficit is about 20% of TDEE — for a 2,759 kcal TDEE that is roughly 552 kcal/day, or a target of about 2,207 kcal. Because roughly 3,500 kcal equals about 1 lb of fat, a 552 kcal/day deficit is about 1.1 lb/week. Do not set goal calories below your BMR: very low intake is hard to sustain and can backfire. This is a fitness estimate, not medical or dietary advice.
TDEE is not fixed. As you lose weight you carry less mass to move and maintain, so your BMR falls, and the body also downregulates energy use somewhat (adaptive thermogenesis). The practical effect is that the same calorie target produces a smaller and smaller deficit over time, so weight loss slows. Recalculate your TDEE roughly every 10 lb (or ~5 kg) with your new weight, rather than treating the first number as permanent.
TDEE and goal calories tell you how much to eat; macros tell you what those calories should be made of — protein, carbohydrate and fat. Once you have your goal calories, use a macro calculator to split them (a common approach sets protein first — often around 0.7–1 g per lb of body weight — then divides the rest between carbs and fat). This tool hands off directly to the Macro Calculator and a protein-intake target.
Method, formulas & references
Methodology: BMR (Mifflin-St Jeor 1990) = 10·kg + 6.25·cm − 5·age + 5 (men) / − 161 (women); Harris-Benedict (revised) uses its own constants and tends to overestimate 5–15%; Katch-McArdle = 370 + 21.6 × lean-kg (lean-kg = weight × (1 − body-fat%)). TDEE = BMR × activity factor (1.2, 1.375, 1.55, 1.725, 1.9); goal calories = TDEE × (1 + goal%). Roughly 3,500 kcal ≈ 1 lb of fat. Units kg/lb and cm/in convert with fixed factors. All calculations run client-side and nothing is stored. A fitness estimate — the activity factor is the biggest variance — not medical or dietary advice.
Cross-links
How we calculate this
Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.
BMR is estimated with the Mifflin-St Jeor, Harris-Benedict or Katch-McArdle equation and multiplied by an activity factor to give TDEE; goal calories = TDEE × (1 + goal%). This is a general fitness estimate — the activity factor is the biggest source of variance, and you should not set goal calories below your BMR. It is general fitness guidance, not medical or dietary advice.
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