TDEE Calculator

How to use the calculator and read the results

Choose US or metric units, then enter your age, sex, height and weight and pick the activity level that best describes a typical week. Height follows the unit system you chose (feet and inches, or centimetres and metres), while the weight unit follows the kg / lb selector next to the weight box. Weight is the only required number; a blank age or height is treated as zero, which will understate the answer, so fill them in.

The table lists six lines:

• TDEE: the Calories per day that keep your weight roughly steady at your stated activity level (maintenance).
• To lose and To gain rows: your TDEE minus or plus a fixed amount, as targets to plan around. In US units the lines are labelled in pounds per week, in metric units in kilograms per week.
• BMR: your basal metabolic rate, the Calories your body would burn in a day of complete rest.

Rows marked with an asterisk are planning targets built by adding or subtracting a flat 500 or 1,000 Calories. They are starting points to adjust against real-world results, not prescriptions.

What TDEE measures

Total daily energy expenditure is the energy you use in 24 hours, expressed in Calories (kilocalories). It adds up four parts:

• Basal metabolic rate (BMR): keeping the heart beating, lungs working, body warm and tissues repaired. For most people this is the largest share, often around two-thirds of the total.
• Thermic effect of food: the energy spent digesting, absorbing and storing what you eat, commonly put at roughly a tenth of intake.
• Non-exercise activity: walking to the shop, standing, fidgeting, housework, carrying children. It varies a lot between people and jobs.
• Exercise: deliberate training such as running, cycling or lifting.

Intake equal to TDEE keeps weight stable over time, intake below it produces a deficit and intake above it a surplus. That simple balance is why TDEE is the usual first step in planning a diet; the BMR calculator covers the resting part alone, and the calorie calculator turns the result into goals.

The formula behind the numbers

The calculator first estimates BMR with the Mifflin-St Jeor equation, which studies of healthy adults have found to be among the more accurate predictive equations. Weight is in kilograms, height in centimetres and age in years.

BMR (men) = 10 × weight + 6.25 × height − 5 × age + 5

BMR (women) = 10 × weight + 6.25 × height − 5 × age − 161

Then it scales BMR by an activity factor:

TDEE = BMR × activity factor

Because the equation subtracts 5 Calories for each year of age, the same person burns about 150 fewer Calories a day at 60 than at 30. The sex term adds 166 Calories between the two formulas at identical size.

Worked example

A 30-year-old man is 5 ft 10 in tall, weighs 170 lb and trains lightly one to three times a week.

1. Convert units: 170 lb × 0.45359 = 77.11 kg, and 5 ft 10 in = 70 in × 2.54 = 177.8 cm.
2. BMR = 10 × 77.11 + 6.25 × 177.8 − 5 × 30 + 5 = 771.1 + 1,111.25 − 150 + 5 = 1,737.4, shown as 1,737 Calories.
3. TDEE = 1,737.4 × 1.375 = 2,388.9, shown as 2,389 Calories.
4. Subtracting 500 gives 1,889 Calories for the first loss target, and subtracting 1,000 gives 1,389.

So eating about 2,400 Calories a day should hold this man's weight steady, while 1,900 would put him on track for a gradual loss.

Using TDEE for weight loss or weight gain

A common rule of thumb says a pound of body fat holds about 3,500 Calories, so a daily shortfall of 500 loses roughly a pound a week; in metric terms a kilogram is usually put near 7,700 Calories. Treat this as an approximation. Weight also moves with water, glycogen and the gradual slowing of metabolism as you get lighter, so real progress is rarely a straight line.

Choose the size of the deficit with your starting point in mind. Take a 35-year-old woman who is 168 cm tall, weighs 62 kg and is sedentary. Her BMR is 10 × 62 + 6.25 × 168 − 5 × 35 − 161 = 1,334 and her TDEE is 1,334 × 1.2 = 1,601. A 500 Calorie deficit would leave only 1,101 Calories a day, which is low enough that it is hard to meet nutrient needs. A smaller deficit, or a more active routine (at a moderate level her TDEE is 2,068), is the more sensible route.

For gaining, the surplus rows add 500 and 1,000 Calories. By the 3,500 Calorie rule a 500 surplus corresponds to about a pound a week, so the half-pound label is cautious; in practice a smaller surplus is usually enough, and only part of any gain is muscle. Once your intake is set, the macro calculator, protein intake calculator and weight loss calorie calculator help divide and time it.

Adults are often advised not to eat below about 1,200 Calories a day (women) or 1,500 (men) without medical supervision. These results are estimates for general information, not medical or dietetic advice; see the disclaimer.

How accurate is it, and what is typical?

Predictive equations are averages. Even the better ones miss the measured resting rate of a fair share of individuals by more than 10%, and the activity multipliers are broad brackets. The most common mistake is picking an activity level that is too high; if you hesitate between two levels, choose the lower one, then track your weight and average intake for two to three weeks and adjust by 100 to 200 Calories at a time.

For context, national dietary guidance estimates that adult women need somewhere between roughly 1,600 and 2,400 Calories a day and adult men between roughly 2,000 and 3,000, with the lower end for older and sedentary people and the upper end for young, active ones. Teenagers who are still growing, pregnant or breastfeeding women, and very muscular people can fall outside these ranges; the EER calculator uses a different set of equations that is worth comparing.