Total Daily Energy Expenditure is the number of calories your body burns in 24 hours, combining your basal metabolic rate (BMR) with activity, exercise, and digestion. Eating near your TDEE maintains weight; eating below it leads to loss and above it to gain.

How accurate is the Mifflin-St Jeor equation?

Mifflin-St Jeor is considered one of the most accurate general-use BMR equations, typically within about 10% of measured values for most adults. Individual metabolism varies, so treat the output as a starting point and adjust based on two to three weeks of real-world weight trends.

How large should my calorie deficit be?

A deficit of 500 calories per day targets roughly 0.45 kg (1 lb) of loss per week. Deficits beyond about 25% of TDEE increase muscle loss, hunger, and adherence problems. Slower cuts of 250-300 calories are easier to sustain.

What macro split should I use?

A common evidence-based starting point is 30% protein, 40% carbohydrate, and 30% fat. Prioritize protein first (about 1.6-2.2 g per kg of body weight when training), then fill remaining calories with carbs and fats per preference.

Health & fitness tool

TDEE Calculator

Find out how many calories your body actually burns each day. This calculator uses the Mifflin-St Jeor equation for BMR, applies your activity level for TDEE, and shows calorie targets for cutting, maintaining, or building muscle — with suggested macros for each goal.

Units Sex Age

Height (cm) Weight (kg)

Activity level

BMR (at rest) 0

TDEE (maintenance) 0

Mild cut (−250 kcal) 0

Standard cut (−500 kcal) 0

Lean bulk (+250 kcal) 0

Macro split at maintenance —

Next steps

Turning Your Number Into a Plan

Track for two weeks, then adjust

Weigh yourself daily under the same conditions and compare weekly averages. If your weight is flat after two weeks, you are eating at maintenance — adjust intake by 100–200 calories in your intended direction rather than making big jumps.

Protect protein when cutting

In a deficit, prioritize 1.6–2.2 g of protein per kg of body weight and keep resistance training. This helps preserve lean mass so more of the weight you lose is fat.

Recount as weight changes

TDEE is not fixed: every few kilograms of change shifts your BMR. Recalculate after every 4–5 kg (or 10 lbs) of progress to keep targets accurate.

Activity multipliers are estimates

Most people overestimate exercise burn. If you are between two activity levels, choose the lower one and adjust based on results rather than the gym clock.

FAQ

TDEE & Calorie Questions

What is the difference between BMR and TDEE?

BMR is the energy your body uses at complete rest just to stay alive — breathing, circulation, cell repair. TDEE adds everything else: movement, exercise, and the thermic effect of food. TDEE is the number to compare your daily intake against.

Which BMR formula does this use?

The Mifflin-St Jeor equation: men, 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5; women, the same but − 161. It is generally more accurate than the older Harris-Benedict equation for modern populations.

How fast can I safely lose weight?

Generally 0.5–1% of body weight per week. That is about 0.5 kg (1 lb) weekly for most people. Faster loss is possible short-term but increases muscle loss, fatigue, and rebound risk.

Why am I not losing at my calculated deficit?

Common causes: portion tracking drift, weekend intake wiping out weekday deficits, overestimated activity, or water-weight masking fat loss for one to two weeks. Audit intake for a week with a food scale before changing targets.

Should I eat back exercise calories?

If you selected an accurate activity level, no — exercise is already included in your TDEE. Only add extra calories for unusually long or intense sessions that clearly fall outside your normal weekly routine.

Is this medical advice?

No. Estimates are for general education. If you are pregnant, under 18, managing a medical condition, or have a history of disordered eating, consult a qualified healthcare professional before changing your intake.

Disclaimer

Health Estimate Disclaimer

This calculator provides educational estimates only and is not medical, nutritional, or diagnostic advice. Individual needs vary. Consult a healthcare professional before starting any diet or exercise program.