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TDEE Calculator Online
Use this free TDEE calculator online to find how many calories you burn in a day. Enter your sex, age, height, weight, and activity level, and it works out your BMR — the calories you burn at rest — then multiplies it by your activity to give your total daily energy expenditure, plus targets for losing, maintaining, and gaining weight.
Weigh yourself in the morning, before eating, for the most consistent number. Pick the activity level that matches your typical week, not your busiest day.
| Target | Calories per day |
|---|---|
| BMR (at complete rest) | 1,783 |
| TDEE (maintenance) | 2,763 |
| Mild weight loss (−250 cal) | 2,513 |
| Weight loss (−500 cal) | 2,263 |
| Weight gain (+500 cal) | 3,263 |
How it works
Your body burns calories all day, even when you are doing nothing. The largest share goes to keeping you alive: your heart beating, your lungs breathing, your brain thinking, and your body warm. That resting burn is called your basal metabolic rate, or BMR, and it usually accounts for 60 to 70 percent of everything you burn in a day. On top of it sit the calories for moving around, working, digesting food, and exercising. Add them all together and you get your total daily energy expenditure — your TDEE. Eat exactly your TDEE and your weight stays steady; eat less and you lose weight; eat more and you gain it.
Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161
TDEE = BMR × activity factor (1.2 to 1.9)
This calculator uses the Mifflin-St Jeor equation, the formula dietitians and researchers rely on most, because it predicts resting calorie burn more accurately than older formulas for most adults. It takes four inputs: weight, height, age, and sex. Weight and height carry the most weight in the formula — a heavier, taller body burns more at rest — while age slowly lowers the result, because metabolism eases off as we get older. Men burn slightly more than women of the same size, which is why the two formulas differ by 166 calories. Pounds convert to kilograms (÷ 2.20462) and inches to centimeters (× 2.54) before the formula runs.
The activity factor turns your resting burn into your real daily burn. The factors come from standard nutrition practice: 1.2 for a sedentary day, 1.375 for light exercise one to three days a week, 1.55 for moderate exercise three to five days a week, 1.725 for hard exercise six to seven days a week, and 1.9 for a physically demanding job or twice-a-day training. Be honest here, because this is where most estimates go wrong — people remember their hardest week, not their average one. If you are between two levels, pick the lower one.
The calorie targets in the table come straight from your TDEE. Maintenance is your TDEE itself. Weight loss subtracts 500 calories a day, which adds up to about 3,500 calories a week — roughly a pound of body fat. A gentler 250-calorie deficit loses about half a pound a week and is easier to keep up for months. Weight gain adds 500 calories a day for roughly a pound a week, which suits someone building muscle alongside strength training. These are starting points: eat at your target for two to three weeks, watch the scale trend, and adjust by 100 to 200 calories if it is flat.
Two things the formula cannot see are worth knowing. First, muscle burns more than fat at rest, so two people of the same weight can have different BMRs — the formula gives an average for your size. Second, your TDEE falls as you lose weight, because a lighter body costs fewer calories to run.
Worked example
A 30-year-old man weighs 180 pounds, is 5 feet 10 inches tall, and exercises moderately three to five days a week. He wants to lose about a pound a week.
Step 1: Convert to metric — 180 ÷ 2.20462 = 81.65 kg, and 70 inches × 2.54 = 177.8 cm.
Step 2: Work out his BMR — 10 × 81.65 + 6.25 × 177.8 − 5 × 30 + 5 = 816.5 + 1,111.3 − 150 + 5 = 1,783 calories.
Step 3: Multiply by his activity factor — 1,783 × 1.55 = 2,763 calories per day. That is his TDEE.
Step 4: Subtract 500 for weight loss — 2,763 − 500 = 2,263 calories per day.
The result is a TDEE of 2,763 calories per day, with a weight-loss target of 2,263 calories a day. That is exactly what the calculator shows for these inputs.
FAQ
What is TDEE?
TDEE stands for total daily energy expenditure — the number of calories your body burns in a full day, including everything from keeping your heart beating to walking, working, and exercising. It starts with your BMR, the calories you burn at complete rest, and multiplies it by an activity factor. A 30-year-old man weighing 180 pounds and 70 inches tall has a BMR of about 1,783 calories and a TDEE of about 2,763 calories at a moderately active level.
How many calories should I eat to lose weight?
A common starting point is 500 calories below your TDEE, which is roughly a pound of fat loss per week, since a pound of body fat stores about 3,500 calories. If your TDEE is 2,763 calories, that means eating about 2,263 calories a day. A 250-calorie deficit works too and is easier to stick with; a deficit above 750 to 1,000 calories a day is best discussed with a doctor or dietitian.
What activity level should I choose?
Choose the level that matches your typical week, not your busiest day. Sedentary means a desk job with little exercise. Lightly active means light exercise one to three days a week. Moderately active means moderate exercise three to five days a week. Very active means hard exercise six to seven days a week. Extra active means a physically demanding job or training twice a day.
Is the Mifflin-St Jeor equation accurate?
It is the most accurate widely used equation for most adults, usually landing within about 10 percent of the value measured in a laboratory. It is less accurate for very muscular people, because muscle burns more calories than fat, and for people with a lot of body fat, for the opposite reason. Treat the result as a starting point: eat at that level for two to three weeks, watch your weight trend, and adjust up or down by 100 to 200 calories.
Why does my TDEE change as I lose weight?
Because a lighter body burns fewer calories — there is simply less of you to keep warm and move around, and the Mifflin-St Jeor equation uses your current weight. After losing 10 or 15 pounds, recalculate your TDEE with your new weight, or your old calorie target may stop being a deficit. The same applies when gaining weight.