Calorie / TDEE Calculator
Basal Metabolic Rate (Mifflin-St Jeor) and Total Daily Energy Expenditure by activity level
Frequently Asked Questions
Total Daily Energy Expenditure (TDEE) — the actual number of calories someone burns in a typical day, including all activity, not just resting metabolism — is BMR multiplied by an activity-level factor, and picking the wrong activity level is the single biggest source of an inaccurate TDEE estimate.
Why activity level is where most people go wrong
BMR is a fixed baseline for a given weight, height, age, and sex — but the activity multiplier applied to it varies substantially depending on how physically active someone genuinely is day to day, ranging from sedentary (little to no exercise, desk job) through lightly active, moderately active, very active, up to extremely active (intense daily exercise or physically demanding work). People frequently overestimate their own activity level, self-selecting a category that reflects their intentions or occasional workouts rather than their actual typical week — since the multiplier difference between adjacent activity levels is substantial, this overestimation directly and meaningfully inflates the calculated TDEE, and consequently any calorie target built on top of it.
A worked example
The identical BMR run through a "sedentary" multiplier versus a "very active" multiplier produces TDEE estimates that can differ by a large margin — for someone who actually exercises a few times a week but otherwise has a desk job and mostly sedentary daily routine, selecting "very active" (because of those workouts) rather than a more moderate category systematically overstates real daily calorie burn, which in turn overstates how much they can eat while still losing or maintaining weight.
How this connects to your other health calculations
TDEE is the foundation for setting an actual calorie target — a deficit for weight loss, a surplus for weight gain, or TDEE itself for maintenance — and once a calorie target is set, the Macro Calculator, Protein Calculator, and Carbohydrate Calculator break that total calorie figure down into specific macronutrient targets.
Common mistakes
Selecting an activity level based on aspirational or occasional exercise rather than a realistic average of an actual typical week is the most common and most consequential mistake — being honest about a genuinely typical week (including the sedentary days, not just the workout days) produces a far more accurate TDEE than assuming every day looks like a workout day.