How to calculate your TDEE

What TDEE actually measures

TDEE stands for Total Daily Energy Expenditure: the total number of calories your body burns in a typical day, from breathing and pumping blood to walking, working, and training. It is the single most useful number in any weight plan, because eating below it, at it, or above it is what drives fat loss, maintenance, or gain.

TDEE is built from four parts. The largest by far is your resting metabolism, the energy you would burn lying still all day. On top of that sits the calories burned digesting food, the calories from deliberate exercise, and the calories from everyday movement like fidgeting, standing, and chores. You cannot measure all of that at home, so we estimate the resting piece with a formula and scale it up with an activity factor.

• Resting metabolism (BMR): usually 60 to 70 percent of the total
• Thermic effect of food: roughly 10 percent, from digestion
• Exercise activity: your workouts
• Non-exercise activity: walking, standing, fidgeting, daily life

Step 1: Find your BMR with Mifflin-St Jeor

Basal Metabolic Rate (BMR) is the calories you burn at complete rest. The Mifflin-St Jeor equation is the modern standard because it tracks real-world resting metabolism more closely than older formulas for most people. It uses weight in kilograms, height in centimeters, and age in years, with a different constant for men and women.

If you think in pounds and feet, convert first: divide pounds by 2.205 for kilograms, and multiply inches by 2.54 for centimeters. The whole equation is just multiplication and addition, so you can run it on any phone calculator or let the tool do it.

• Men: BMR = 10 x kg + 6.25 x cm - 5 x age + 5
• Women: BMR = 10 x kg + 6.25 x cm - 5 x age - 161
• The only difference between the two is the final number: +5 for men, -161 for women

Step 2: Multiply by your activity factor

BMR is only rest. To reach TDEE you multiply it by an activity factor that reflects how much you move. The honest part here is picking the right one: most people overestimate. A few gym sessions a week is moderate, not very active. If your job is a desk and your evenings are a couch, you are sedentary even if you train hard three times a week.

Choose the level that matches a normal week, then multiply. When you are between two levels, round down. Overstating activity is the most common reason a plan stalls, because it inflates your calorie target from the start.

• Sedentary (little or no exercise): BMR x 1.2
• Lightly active (light exercise 1 to 3 days a week): BMR x 1.375
• Moderately active (moderate exercise 3 to 5 days): BMR x 1.55
• Very active (hard exercise 6 to 7 days): BMR x 1.725
• Extra active (physical job or two-a-day training): BMR x 1.9

A worked example, start to finish

Take a 30-year-old man who is 5 feet 10 inches (178 cm) and weighs 175 pounds (about 79.4 kg), training moderately three to four days a week.

First the BMR: 10 x 79.4 = 794, plus 6.25 x 178 = 1,112.5, minus 5 x 30 = 150, plus 5 for being male. That is 794 + 1,112.5 - 150 + 5 = 1,761.5, which rounds to about 1,762 calories. That is what he would burn doing nothing all day.

Now the activity factor. Moderately active means multiply by 1.55: 1,762 x 1.55 = 2,731 calories. That is his TDEE, the calories that hold his weight steady. From here, every goal is a shift up or down from 2,731.

Use your TDEE to lose, maintain, or gain

One pound of body fat stores roughly 3,500 calories, so a daily gap of about 500 calories adds up to close to a pound a week. That rule of thumb is where deficit and surplus targets come from. It is an approximation, not a law: water weight and metabolic changes make the scale bounce around week to week.

To lose weight, subtract 500 from your TDEE. Our example man eats about 2,231 calories to lose roughly a pound a week. To maintain, eat at your TDEE, 2,731. To gain, add a surplus, but keep it modest: 250 to 500 over TDEE, so about 3,000 to 3,200, adds muscle without piling on excess fat. Aggressive surpluses mostly add fat.

Recalculate as your weight changes. TDEE falls as you get lighter, so a deficit that worked at 175 pounds is smaller at 160. Re-run the numbers every 8 to 12 pounds, or whenever progress clearly stalls for two to three weeks.

• Lose weight: TDEE minus 500 (about 1 lb per week)
• Maintain: eat at TDEE
• Gain: TDEE plus 250 to 500 for lean gains
• Do not drop below about 1,500 calories (men) or 1,200 (women) without medical supervision

Turn calories into macros

A calorie target tells you how much to eat; macros tell you what. The one that matters most for body composition is protein, which protects muscle in a deficit and keeps you full. A common target is about 0.7 to 1 gram per pound of body weight. Fat should stay high enough for hormone health, usually 0.3 to 0.4 grams per pound, and carbohydrates fill whatever calories remain to fuel training.

For the example man cutting on 2,231 calories: set protein around 150 grams (600 calories), fat around 60 grams (540 calories), and the remaining 1,091 calories as carbohydrates, about 273 grams. Protein and carbs carry 4 calories per gram and fat carries 9, which is why the fat number looks small but eats up a lot of the budget.

• Protein: 0.7 to 1 g per lb of bodyweight, at 4 cal/g
• Fat: 0.3 to 0.4 g per lb, at 9 cal/g
• Carbs: the calories left over, at 4 cal/g
• Set protein first, then fat, then let carbs fill the rest

Common mistakes

TDEE math is simple, but a few predictable errors send people off course. Watching for these keeps your estimate honest and your results on track.

• Overrating your activity level. Picking very active when you sit at a desk inflates your target by hundreds of calories and stalls progress before you start.
• Treating the number as exact. Formulas estimate the average person; your real burn can be 5 to 10 percent higher or lower. Use the scale over two to three weeks as the true test and adjust.
• Never recalculating. As you lose weight your TDEE drops, so a deficit slowly shrinks to maintenance if you never update it.
• Not tracking intake honestly. Untracked bites, oils, and drinks quietly erase a 500-calorie deficit. The math only works if the food log is accurate.
• Cutting too hard. Slashing far below TDEE costs muscle, energy, and adherence, and rarely beats a steady 500-calorie deficit over time.