TDEE Calculator
Right now, even sitting — your body is burning calories. Let’s find out exactly how many it burns in a whole day, so you can finally stop guessing.
Calculate Your TDEE
Be honest. The math works better that way.
What Is TDEE?
Here’s the thing. Your body — this remarkable, slightly ridiculous machine you’ve been hauling around since birth — is burning energy all the time. While you sleep. While you argue with someone on the internet. While you sit in a meeting that could have been an email. All the time.
Total Daily Energy Expenditure (TDEE) is simply the total number of calories your body burns in one full day. All of them. Every last little calorie that went up in the quiet furnace of being alive.
And it turns out, this total is made up of four distinct components — each one doing its own humble, essential work:
BMR — Basal Metabolic Rate
This is the big one. The energy your body demands just to keep the lights on: breathing, pumping blood, growing new cells, maintaining a body temperature that doesn’t alarm nearby strangers. BMR accounts for a whopping 60–70% of your total daily burn. You’re doing most of your caloric work by simply existing. Which, if you think about it, is kind of beautiful.
EAT — Exercise Activity Thermogenesis
The calories you burn on purpose. The gym. The run. The structured suffering you’ve chosen to inflict upon yourself in the name of self-improvement. This includes any deliberate exercise — lifting, cycling, swimming, HYROX, chasing your dog who got off the leash again.
NEAT — Non-Exercise Activity Thermogenesis
This is the sneaky one. All the energy you burn through movements you don’t think of as “exercise” — walking to the fridge, fidgeting, gesticulating wildly during a story no one asked to hear, pacing while on the phone. NEAT varies wildly between people and can make a surprisingly enormous difference in total daily burn.
TEF — Thermic Effect of Food
It takes energy to process energy. Your body burns calories just digesting what you eat — roughly 10% of your total intake. Protein, it turns out, costs the most to digest. Which is one of those satisfying little facts that makes the universe feel briefly organized.
Why Knowing Your TDEE Matters
Here’s where we get honest with each other. Most nutrition plans fail — not because people lack willpower or discipline or some mythical inner toughness — but because they’re built on guesses. You’re told to “eat less” or “eat clean” without anyone ever telling you how much your body actually needs.
TDEE fixes that. It gives you a number. A real, specific, personalized number. And from that number, everything else becomes remarkably simple (not easy, mind you — simple). Eat fewer calories than your TDEE and you lose weight. Eat more and you gain weight. Eat right at it and you stay roughly the same. That’s not opinion. That’s thermodynamics. And thermodynamics, unlike most things in life, does not care about your feelings.
How Is TDEE Calculated?
TDEE is estimated in two steps. The first step is calculating your Basal Metabolic Rate — the energy you’d burn if you just lay in bed all day doing absolutely nothing (which, honestly, some Sundays). The second step is multiplying that number by an activity factor that accounts for, you know, the fact that you do actually get out of bed.
The Mifflin-St Jeor Equation
This calculator uses the Mifflin-St Jeor equation. It was published in 1990 by a couple of researchers who, one imagines, looked at all the existing BMR formulas and thought: “We can do better.” And they did. The Academy of Nutrition and Dietetics considers it the most reliable BMR equation for most adults, and multiple studies have validated its accuracy.
It takes four inputs — your weight, height, age, and biological sex — and produces a number that represents the calories you’d burn in a coma. (We say this with love.)
Women: BMR = (10 × weight in kg) + (6.25 × height in cm) − (5 × age) − 161
Once we have your BMR, we multiply it by an activity factor — a number between 1.2 and 1.9 — to account for the fact that you are, presumably, a person who moves around:
Other BMR Equations
Mifflin-St Jeor is the star of this particular show, but it’s not the only equation out there. The Harris-Benedict equation (revised in 1984, like a second edition of a textbook no one was fully satisfied with the first time) is another popular choice. And the Katch-McArdle formula factors in lean body mass, making it potentially more accurate for people who are particularly lean or muscular. If you know your body fat percentage, Katch-McArdle might be worth a look. If you don’t, Mifflin-St Jeor has got you covered.
Activity Factors Explained
This is where things get personal. Your activity multiplier is, in a sense, the story you tell about your life — translated into a decimal. And here’s the uncomfortable truth: most of us are unreliable narrators of our own activity levels. We remember the one intense workout we did last Tuesday and conveniently forget the four days we spent watching Netflix in what can only be described as a committed horizontal position.
So. Be honest. The number will thank you.
| Level | Multiplier | Description |
|---|---|---|
| Sedentary | 1.2 | Desk job, little or no exercise. No judgment — just math. |
| Lightly Active | 1.375 | Light exercise 1–3 days per week. A few walks. Some effort. |
| Moderately Active | 1.55 | Moderate exercise 3–5 days per week. You show up regularly. |
| Very Active | 1.725 | Hard exercise 6–7 days per week. People notice. Your laundry pile is alarming. |
| Extremely Active | 1.9 | Twice-daily training or physical labor + exercise. You are, respectfully, a machine. |
Pro Tip: Most People Overestimate
This is not a personal attack. It’s a well-documented phenomenon. Research consistently shows people overestimate their activity level by one full tier. So if your gut says “Moderately Active,” your gut might be engaging in a small, well-intentioned act of self-deception. Start one level lower. Track for 2–3 weeks. Adjust from there. The truth, as always, reveals itself on the scale.
How to Use Your TDEE
Okay. You’ve got a number. Congratulations. Now what? Well, that depends entirely on what you’re trying to do with this one wild and precious body of yours. Your TDEE is the foundation — the load-bearing wall — upon which any sensible nutrition strategy is built.
For Weight Loss (Calorie Deficit)
To lose body fat, you eat fewer calories than your TDEE. That’s it. That’s the whole secret. A moderate deficit of 300–500 calories per day is sustainable for most people and typically produces a loss of about 0.5–1 pound per week. Could you go more aggressive? Sure. But extreme deficits tend to end the way extreme things usually end — badly. Muscle loss, metabolic adaptation, the overwhelming desire to eat an entire pizza at 11 PM on a Wednesday. Moderate wins.
For Muscle Gain (Calorie Surplus)
Building muscle requires a surplus — eating slightly more than your TDEE. A surplus of 250–500 calories per day, combined with progressive resistance training, gives your body the raw materials it needs to construct new tissue. Think of it like a construction project: you can’t build an addition to your house without buying extra lumber. The lumber, in this metaphor, is food. (We are aware this metaphor has limitations.)
For Maintenance
Sometimes the goal is simply to stay where you are. And that’s not a lack of ambition — it’s a legitimate strategy. Eating at your TDEE keeps your weight stable. This is useful during recovery, during body recomposition phases (where you’re building muscle and losing fat at roughly the same weight), or during those stretches of life when you’ve got enough going on and the last thing you need is to be hungry about it too.
What Is a Calorie Deficit?
A calorie deficit is what happens when you eat fewer calories than you burn. If your TDEE is 2,400 and you eat 1,900, you’re in a 500-calorie deficit. Do that every day for a week and that’s roughly 3,500 calories unaccounted for — which is approximately the amount of energy stored in one pound of body fat. So, one week, one pound. Give or take. The body is not a perfect math problem, but it is a reasonably cooperative one.
Can You Increase Your TDEE?
Yes, and here’s the good news: you have more control over this number than you might think. Building lean muscle through resistance training raises your BMR, because muscle tissue is metabolically expensive to maintain. (Fat, by contrast, is very cheap to maintain. Fat is the roommate who never pays utilities.) Increasing your daily step count and general movement — your NEAT — can add hundreds of extra calories to your daily expenditure without you ever setting foot in a gym. And eating adequate protein slightly raises your thermic effect of food, which means you burn a bit more just digesting it. Small things, compounding over time, making a real difference. The way most good things work.
TDEE vs. BMI
People confuse these two all the time, and it’s worth clearing up, because they measure entirely different things and serve entirely different purposes — like confusing a speedometer with a fuel gauge. Both live on your dashboard, but they’re telling you very different stories.
BMI (Body Mass Index) takes your weight and your height and produces a ratio. That’s it. It doesn’t know if you’re muscular, sedentary, carrying a backpack full of rocks, or any other relevant detail about your life. A bodybuilder and an overweight couch potato can have the same BMI, which tells you something important about the limitations of BMI.
TDEE, on the other hand, tells you something you can actually use: how much energy your specific body, with your specific habits, burns in a day. From that number, you can build a plan. BMI tells you where you fall on a chart. TDEE tells you what to do about it.
Both tools have their place. But if you’re trying to figure out how much to eat, TDEE is far more actionable than BMI. And “actionable” is what we’re going for here. We’ve all had enough of numbers that just sit there making us feel bad.
Frequently Asked Questions
TDEE stands for Total Daily Energy Expenditure. It’s the total number of calories your body burns in a 24-hour period — everything from your Basal Metabolic Rate (the energy of just being alive) to your physical activity, your non-exercise movement (NEAT), and even the energy it takes to digest your food (TEF). Think of it as the full invoice your body sends you every day for the privilege of existing.
First, we estimate your BMR using the Mifflin-St Jeor equation — a formula that takes your age, sex, height, and weight and turns them into a calorie number. Then we multiply that number by an activity factor (ranging from 1.2 for people who mostly sit, to 1.9 for people who mostly don’t). The result is your TDEE. It’s an estimate, not a prophecy, but it’s a very good starting point.
BMR is what you’d burn if you stayed in bed all day doing absolutely nothing — the bare minimum for organ function, breathing, and not ceasing to exist. TDEE is your BMR plus everything else: exercise, walking, fidgeting, digesting. Your TDEE is always higher than your BMR, because even the most sedentary among us do occasionally stand up.
Honest answer? It’s a good estimate — typically within 10–15% of your actual expenditure. The equations are solid, but they were built from population averages, and you are not an average. You are a specific, unrepeatable person. So use your TDEE as a starting point, track your weight for 2–4 weeks, and adjust. Reality is the best calculator of all.
You can. Build muscle through resistance training — muscle burns more calories at rest than fat does, even while you sleep. Move more throughout the day (walk, take stairs, pace during phone calls). Eat adequate protein, which costs your body more energy to digest. These aren’t dramatic overnight changes; they’re small, stacking advantages that compound into something real.
A calorie deficit is what happens when you eat fewer calories than your body burns. If your TDEE is 2,500 and you eat 2,000, you’ve got a 500-calorie deficit. Do that consistently and your body starts dipping into stored energy (fat) to make up the difference. A moderate deficit of 300–500 calories per day is the sweet spot for most people — aggressive enough to produce results, gentle enough that you don’t lose your mind.
Every 4–6 weeks, or whenever something significant changes — your weight shifts by 5+ pounds, your activity level changes, your life rearranges itself in some meaningful way. Your body is not static. It’s adapting all the time. Your nutrition plan should adapt with it, because the number that was right for you in January might not be right for you in March.
Ready to Put Your TDEE to Work?
You’ve got the number. You understand what it means. Now the only thing left is the doing — which, as you and I both know, is the hard part and also the only part that matters. Go build something with it.