TDEE calculator

TDEE stands for Total Daily Energy Expenditure. It is the total number of calories your body uses in 24 hours. That includes the energy your heart, lungs and brain use at rest, plus everything you do on top of that, like walking to work, cleaning the house and training at the gym.

Think of it as your daily fuel bill. Your number is your own, and it changes over time as your weight, age and activity change.

TDEE is usually split into four parts:

• Basal metabolic rate (BMR): the energy your body needs to keep running at rest. This is the largest part for most people.
• Non exercise activity thermogenesis (NEAT): the energy used for everyday movement that is not a workout, such as walking, chores and fidgeting.
• Exercise activity thermogenesis (EAT): the energy used during planned exercise.
• Thermic effect of food (TEF): the energy used to digest and process what you eat, usually about 10 percent of your daily total.

This calculator estimates your resting rate from your age, sex, height and weight, then applies a multiplier for your activity level. The bar in the result shows how the total splits across those four parts.

They give a reasonable estimate, not an exact measurement. This tool uses the Mifflin St Jeor equation, which is one of the more reliable formulas for estimating resting energy needs in adults.

Even so, two people with the same height, weight and age can burn different amounts. Genetics, hormones, sleep, stress, health conditions and muscle mass all play a part. Treat the number as a place to begin, then adjust based on how your body responds over a few weeks.

Your TDEE is roughly what you spend in a day. A calorie deficit is the gap you create when you eat less than that number, so your body draws on stored energy.

A smaller, steady deficit is generally easier to keep up than a large one, and it is less likely to cost you muscle. Cutting very hard can leave you tired, hungry and short on nutrients, which makes the whole thing harder to stick with.

To a degree, yes. Moving more during the day raises the everyday movement part of your total, and that is often the easiest lever to pull. Adding planned exercise raises it further.

Building muscle can also lift your resting rate a little, since muscle uses more energy than fat to maintain. The effect is real but modest, so it works best alongside more daily movement.

On average, yes, mostly because of differences in average body size and body composition. More muscle means a higher resting rate, since muscle needs more energy to maintain than fat does.

These are averages, though. Age, body size, activity and health all move the number, so there is a wide range within any group.

It is optional. If you know your body fat percentage from a recent scan or measurement, the calculator switches to the Katch McArdle equation, which works from your lean mass rather than your total weight. That can be a closer estimate if you carry more or less muscle than average.

If you are not sure of the number, leave it blank. A guess can push the result further off than using your weight alone.

It can be a useful starting point, but it should not be the only thing you go on. Rather than chasing a specific number on the scale, many providers talk about the weight you can hold comfortably while living a full life. That looks different for everyone.

Before you change how you eat or train, it is worth speaking with a licensed healthcare provider who can look at your full health picture and help you set goals that are realistic and safe for you.