TDEE Calculator

What Is TDEE?

TDEE stands for Total Daily Energy Expenditure. It is the total number of calories your body burns in a full day — everything from keeping your heart beating and your brain running to walking to the kitchen, working out, and even digesting your food.

If you know your TDEE, you know roughly how much to eat to stay the same weight. Eat a little less than that number and you tend to lose weight over time. Eat a little more and you tend to gain. That is why TDEE is the starting point for almost every sensible eating plan: it turns vague advice like “eat less” into a concrete daily target you can actually work with.

Our calculator above gives you that number in seconds. Enter your gender, age, height, weight, and activity level, and it works out your result on the spot. Nothing is stored or sent anywhere — the math runs entirely in your browser.

How the Formula Works

The calculator uses the Mifflin-St Jeor equation, the formula most dietitians and fitness professionals rely on today because it holds up well for the average adult.

It works in two steps. First, it estimates your BMR — your Basal Metabolic Rate. That is the energy your body would use if you lay in bed all day doing nothing: breathing, circulating blood, maintaining body temperature, and keeping your organs running. BMR depends mainly on your weight, height, age, and gender, because larger bodies burn more at rest and metabolism generally slows a little as we get older.

Second, it multiplies your BMR by an activity factor. A desk worker who rarely exercises might multiply by 1.2, while someone training hard almost every day might use 1.725. The result is your TDEE — your maintenance calories.

That is also why two people of the same size can have very different numbers. The formula is the same; the lifestyle is not.

Activity Levels, Explained

Picking the right activity level matters more than most people think, and it is also where most people go wrong. The honest rule is to judge your whole week, not your best day.

Sedentary means a desk job and little or no planned exercise. Lightly active means light exercise one to three days a week, or a job that keeps you on your feet a little. Moderately active means moderate exercise three to five days a week — the most common honest choice. Very active means hard training six or seven days a week. Extra active is reserved for people doing very hard exercise daily or physical labor all day.

If you are unsure, pick the lower option. Most people overestimate how active they are, and an inflated TDEE quietly erases a calorie deficit. You can always adjust later based on what the scale and the mirror tell you over a few weeks.

How to Use Your Number

Start with maintenance. If your goal is to stay the same weight, aim to eat around your TDEE. If you want to lose weight, the calculator also shows a mild deficit of 250 calories and a standard deficit of 500 calories a day. A 500-calorie daily deficit works out to roughly a pound of fat loss per week for most people, which is a steady, sustainable pace. The mild deficit is the better choice if you are already fairly lean, new to tracking, or worried about hunger and energy.

For gaining muscle, the calculator shows a mild surplus of 250 and a larger surplus of 500 calories. A smaller surplus usually means slower but leaner gains, with less fat added along the way.

Whichever target you pick, treat it as a starting estimate, not a verdict. Track your weight for two to three weeks. If it is not moving the way you want, adjust by 100 to 200 calories and keep going. Your body, your routine, and your consistency matter more than any single number.

Why Your TDEE Changes

Your TDEE is not fixed for life. It shifts when your weight changes, because a lighter body burns fewer calories. It shifts when your routine changes — a new active job, a training program, or a long sedentary stretch all move the number. Age nudges it down gradually, and building muscle nudges it up, since muscle tissue uses more energy at rest than fat does.

That is why it is worth recalculating every couple of months, or whenever your weight or routine changes noticeably. A number that was right in January may be a few hundred calories off by summer, and small errors like that are exactly what stall progress.

Frequently Asked Questions

1. What is the difference between BMR and TDEE?

BMR is what your body burns at complete rest, just staying alive. TDEE is BMR plus everything you do — moving, working, exercising, and digesting food. BMR is the foundation; TDEE is the number you actually eat to.

2. How accurate is this calculator?

For most adults it lands within roughly 10 percent of the true value, which is good enough to plan around. Accuracy drops if you are very muscular, very lean, or carrying a lot of body fat, because the formula works from weight and height rather than body composition. Treat the result as a starting point and adjust from real-world progress.

3. Should I use my exercise calories on top of TDEE?

No. Your activity level already includes your exercise, so adding workout calories on top would double-count them. If you use a fitness tracker, do not add its calorie burn to your TDEE target — pick one method and stick with it.

4. How often should I recalculate my TDEE?

Every couple of months, or after a noticeable change in weight or routine — for example, losing 10 pounds, starting a new training program, or switching to a desk job. Small, regular updates keep your target honest.

5. Is a 500-calorie deficit safe?

For most healthy adults, yes — it is the standard, widely recommended pace for gradual weight loss. Very low total intakes (generally under 1,200 calories a day for women or 1,500 for men) are a different story and worth discussing with a doctor or dietitian first.

6. Why does the calculator ask for gender?

Men and women tend to differ in average muscle mass and body composition at the same weight, which affects resting energy use. The Mifflin-St Jeor equation includes a small adjustment for this, which is why the question is there.

Disclaimer: This calculator is for general information only and is not medical advice. Talk to a doctor or registered dietitian before starting a new diet or exercise program, especially if you have a health condition.