Mifflin-St Jeor (1990) is the most accurate of the common BMR formulas in head-to-head studies vs measured RMR. It's the formula most fitness apps and dietitians use today.

How are cut and bulk calculated?

Cut = TDEE × 0.80 (a 20% deficit, ~0.5-0.7 kg/week loss). Bulk = TDEE × 1.15 (a 15% surplus, ~0.25 kg/week gain). Adjust based on your scale trend.

TDEE Calculator

Daily calorie needs using Mifflin-St Jeor BMR and activity multiplier.

Age

Sex

Weight (kg)

Height (cm)

Activity level

BMR (basal)

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TDEE (maintenance)

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Cut (−20%)

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Bulk (+15%)

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Enter age, sex, height, weight and activity level. We compute BMR (Mifflin-St Jeor), apply an activity multiplier for TDEE, and show common cut and bulk targets.

How to use it

Enter age, sex, height, weight
Metric or imperial - pick the tab that matches your scale and measuring tape.
Pick an activity level
Be honest. 'Moderate' is 3-5 actual training sessions per week, not your gym membership.
Read BMR and TDEE
BMR is rest-only; TDEE is your maintenance. Cut and bulk targets give a starting point for body-comp goals.

What is it?

Total Daily Energy Expenditure (TDEE) is your maintenance calorie intake - the number of kilocalories you burn in 24 hours including activity. It's the gateway metric for any deliberate weight change: eat below it to lose, above to gain. The formula is Basal Metabolic Rate (Mifflin-St Jeor) times an activity multiplier from 1.2 (sedentary) to 1.9 (very active).

When to use it

Setting calorie targets for cutting, bulking or maintenance. Adjusting macros for a new training program. Sanity-checking a number a fitness app gave you. Estimating the energy cost of a sedentary office job vs an active manual one.

Common mistakes

Picking too high an activity factor - most people overestimate. 'Sedentary' is most desk jobs. The multiplier is a rough guess; let the scale settle over 2-3 weeks before tuning. Treating the cut number as gospel - your real BMR may be 10% off in either direction. And forgetting muscle mass: very muscular bodies burn more, very lean older bodies less.

FAQ

Why Mifflin-St Jeor?: Mifflin-St Jeor (1990) is the most accurate of the common BMR formulas in head-to-head studies vs measured RMR. It's the formula most fitness apps and dietitians use today.
How are cut and bulk calculated?: Cut = TDEE × 0.80 (a 20% deficit, ~0.5-0.7 kg/week loss). Bulk = TDEE × 1.15 (a 15% surplus, ~0.25 kg/week gain). Adjust based on your scale trend.