TDEE stands for total daily energy expenditure, the total number of calories your body burns in a day. It combines the energy you use at complete rest with the energy spent digesting food, moving around without formal exercise, and working out. Because it captures everything, your TDEE is also your maintenance level, the intake that keeps your weight roughly steady.

What does a TDEE calculator do?

A TDEE calculator estimates how many calories you burn in a typical day. It first works out your basal metabolic rate from your weight, height, age, and sex, then multiplies that by an activity factor that reflects how much you move. The result is a single maintenance number you can use as the anchor for any nutrition or training plan.

What is the difference between BMR and TDEE?

Your basal metabolic rate (BMR) is the energy your body uses at complete rest just to stay alive, such as breathing, circulation, and keeping your cells running. TDEE is BMR plus everything you do on top of it: digesting food, day to day movement, and exercise. TDEE is always larger than BMR, often by 20 to 90 percent depending on how active you are.

How is TDEE calculated?

A TDEE calculator estimates your BMR with an equation such as Mifflin-St Jeor, then multiplies it by an activity multiplier. The multipliers run from about 1.2 for a sedentary lifestyle up to about 1.9 for people who train hard daily or do heavy physical work. BMR times the multiplier gives your total daily energy expenditure in calories.

What is the Mifflin-St Jeor equation?

It is the BMR formula most dietitians favor today. For men, BMR equals 10 times weight in kilograms, plus 6.25 times height in centimeters, minus 5 times age in years, plus 5. For women, the last term is minus 161 instead of plus 5. Research generally finds it more accurate for current populations than the older Harris-Benedict formula.

What is the Harris-Benedict equation and how does it differ?

The Harris-Benedict equation is an older BMR formula, later revised, that uses different coefficients for weight, height, and age. It tends to give a slightly higher BMR than Mifflin-St Jeor for many people. Our TDEE calculator can show both so you can compare. The two usually land within about 100 calories of each other, which is close given they are estimates.

What are the four components of TDEE?

TDEE has four parts. Basal metabolic rate is the resting baseline and the largest share. The thermic effect of food (TEF) is the energy used to digest and process meals, roughly 10 percent of intake. NEAT, or non-exercise activity thermogenesis, covers everyday movement like walking and fidgeting. Exercise activity is the calories burned in deliberate workouts.

What are the activity multipliers?

The standard multipliers applied to BMR are 1.2 for sedentary (little or no exercise), 1.375 for lightly active (light exercise one to three days a week), 1.55 for moderately active (three to five days), 1.725 for very active (six or seven days), and 1.9 for extremely active (hard daily training or a physical job). Your BMR times the right multiplier gives your TDEE.

Which activity level should I choose?

Choose the multiplier that matches an average week, not your hardest day. Most people who sit at a desk and train a few times a week land around moderately active. Overestimating is the most common error, so if you are between two levels, pick the lower one and adjust after watching how your weight actually behaves over a few weeks.

How accurate is a TDEE calculator?

A TDEE calculator gives a good estimate, typically within a few hundred calories, but not an exact reading. The equations rely on population averages and cannot see your true muscle mass, genetics, or hormones. The most accurate figure comes from using the estimate as a start, then tracking your weight for two or three weeks and refining the number from real results.

What is the thermic effect of food?

The thermic effect of food, or TEF, is the energy your body spends digesting, absorbing, and storing the nutrients in a meal. It accounts for roughly 10 percent of the calories you eat, though protein has a higher effect than carbohydrates or fat. TEF is one of the four parts of your total daily energy expenditure and is already folded into the activity multiplier.

NEAT stands for non-exercise activity thermogenesis, the calories you burn through everyday movement that is not formal exercise: walking to the shops, cleaning, standing, typing, and even fidgeting. NEAT varies a lot between people and can differ by several hundred calories a day, which is a big reason two people with the same stats can have different TDEE figures.

How do I use my TDEE to lose or gain weight?

Your TDEE is your maintenance level. To lose weight, eat below it, commonly by about 500 calories a day. To gain, eat above it. To hold steady, eat at it. This tool focuses on finding the maintenance number itself; to turn it into a goal target with a suggested deficit or surplus, use our companion calorie calculator.

Is the ToolFiddle TDEE calculator free and private?

Yes to both. There is no sign-up, no account, no email, and no daily limit, and every feature is open. The whole calculation runs in your browser, so your weight, height, age, and sex stay on your device. Nothing is uploaded to a server, and nothing is stored or logged once you close the tab.

How often should I recalculate my TDEE?

Recalculate whenever your body or routine changes noticeably, since your TDEE shifts with weight and activity. A sensible habit is to run the TDEE calculator again after every 5 to 10 pounds of weight change, or when your training load or job changes, so your maintenance number keeps matching your current life rather than an old snapshot.

TDEE Calculator: Find Your Maintenance Calories

A TDEE calculator estimates your total daily energy expenditure, the total number of calories your body burns across a full day, using your weight, height, age, sex, and activity level. That single number is your maintenance level, the amount you would eat to keep your weight steady, and it is the anchor point for any sensible nutrition or training plan. The ToolFiddle TDEE calculator works it out instantly, shows the result from two respected formulas, breaks the figure into its four parts, and keeps everything you enter on your own device.

This page is about the maintenance number itself: what it means, how it is built, and how far to trust it. We spend most of the space on computing and explaining TDEE clearly, and we keep goal setting lighter, because turning your maintenance figure into a target for losing or gaining weight is exactly what our companion calorie calculator is designed to do. Understand your TDEE well and every other decision about food and exercise gets easier.

What total daily energy expenditure means

Total daily energy expenditure is the sum of all the energy your body uses in 24 hours. Your body is always burning calories, even asleep, to keep your heart beating, your lungs moving, and your cells working. On top of that baseline, you burn more whenever you digest a meal, walk across a room, climb stairs, or train. Add every one of those together and you get your TDEE.

Because it captures everything you burn, TDEE is the same as your maintenance calorie level. If you eat that many calories on average, your weight tends to stay where it is. Eat consistently below it and your body draws on stored energy, so you lose weight over time. Eat consistently above it and the surplus is stored, so you gain. This is the principle of energy balance, and your TDEE is the pivot the whole thing turns on.

That is why so many people look for a reliable TDEE calculator before starting any change to their eating. Without a maintenance number, phrases like "eat less" or "eat more" have no scale. With one, you have a concrete figure to plan against, whether your aim is fat loss, muscle gain, athletic fueling, or simply holding a weight you are happy with. The number does not make decisions for you, but it turns vague intentions into something you can measure.

BMR versus TDEE

People often mix up BMR and TDEE, so it is worth separating them clearly. Basal metabolic rate, or BMR, is the energy your body needs at complete rest, lying still, awake, and not digesting, purely to keep you alive. It is the floor of your daily burn and, for most people, the single largest slice of it. A closely related term, resting metabolic rate, is measured under slightly less strict conditions and comes out a touch higher, but the two are often used interchangeably.

TDEE is BMR plus everything else you do. It always exceeds BMR, and by how much depends on how active you are. A very sedentary person might have a TDEE only about 20 percent above their BMR, while someone who trains hard and moves a lot all day could sit 80 or 90 percent above it. That gap is precisely what the activity multiplier in a TDEE calculator is trying to capture.

So a TDEE calculator really does two jobs in sequence. First it estimates your BMR from your body stats using an equation. Then it scales that BMR up by an activity factor to arrive at your full daily burn. Understanding this two step structure makes the rest of the tool intuitive, because you can see exactly where your number comes from and what would change it.

The four components of your TDEE

Your total daily energy expenditure is built from four parts, and knowing them helps you understand why the number lands where it does.

Basal metabolic rate is the first and largest, usually around 60 to 70 percent of TDEE for a typical person. This is the resting cost of being alive, and it scales mostly with your size and how much lean tissue you carry, which is why muscle mass nudges it upward.

The thermic effect of food, often shortened to TEF, is the energy your body spends digesting, absorbing, and processing what you eat. It runs at roughly 10 percent of the calories you consume. Protein has a notably higher thermic effect than carbohydrates or fat, so a higher protein diet raises this component slightly.

NEAT, non-exercise activity thermogenesis, covers all the movement that is not deliberate exercise: walking to work, cooking, cleaning, taking the stairs, standing, and even fidgeting. NEAT is the most variable part of TDEE and can differ by several hundred calories a day between two similar people, which explains a lot of the difference in how easily people maintain their weight.

The fourth part is exercise activity, sometimes called EAT, the calories burned in intentional workouts such as running, lifting, or cycling. For many people this is actually the smallest slice, smaller than they expect, which is why relying on exercise alone to create a deficit is often disappointing. A TDEE calculator bundles TEF, NEAT, and exercise together inside the single activity multiplier, so you do not enter them separately, but seeing the parts helps you read your number wisely.

The formulas: Mifflin-St Jeor and Harris-Benedict

The ToolFiddle TDEE calculator can estimate your BMR with two well known equations, so you can compare them.

The Mifflin-St Jeor equation, published in 1990, is the one most dietitians use today because studies find it reasonably accurate for modern populations. For men, BMR equals 10 times weight in kilograms, plus 6.25 times height in centimeters, minus 5 times age in years, plus 5. For women, everything is the same except the final constant, which is minus 161 rather than plus 5.

The Harris-Benedict equation is older, first published in 1919 and revised in 1984, and it uses different coefficients. In its revised form, the men's version is 88.362, plus 13.397 times weight in kilograms, plus 4.799 times height in centimeters, minus 5.677 times age in years. The women's version is 447.593, plus 9.247 times weight, plus 3.098 times height, minus 4.330 times age. It often returns a slightly higher BMR than Mifflin-St Jeor.

Whichever BMR you start from, the TDEE step is identical: multiply by your activity factor. Seeing both formulas side by side is useful because it shows that these are estimates with a margin, not precise measurements. If the two equations differ by 80 or 100 calories, that difference is a fair signal of the uncertainty built into any calculated TDEE, and it is a reminder to treat your number as a starting point to refine.

The activity multipliers

The activity factor is the second half of the TDEE calculation, and it has a large effect. These are the standard multipliers applied to BMR:

Sedentary. Little or no exercise, desk job: multiply BMR by 1.2.
Lightly active. Light exercise one to three days a week: multiply BMR by 1.375.
Moderately active. Moderate exercise three to five days a week: multiply BMR by 1.55.
Very active. Hard exercise six or seven days a week: multiply BMR by 1.725.
Extremely active. Very hard daily training or a physically demanding job: multiply BMR by 1.9.

The jump from sedentary to very active can change your TDEE by roughly 40 percent, which is hundreds of calories for most people. That is why choosing the right level matters more than fussing over which BMR formula to use. Because the multiplier folds in NEAT, TEF, and exercise all at once, it is a broad brush, and honest self assessment is the best way to make it accurate.

How to use the ToolFiddle TDEE calculator

The tool returns a maintenance number in seconds, with no account and no waiting. Here is each step.

Choose your units. Select metric (kilograms and centimeters) or imperial (pounds and feet or inches). The tool converts internally, so pick whatever your numbers are in.
Enter your body stats. Type your weight, height, age, and sex. These feed the BMR equation.
Select your activity level. Every level from sedentary to athlete is shown as a row with its own calorie figure, so you see the full range before you choose. Click the row that matches your typical week.
Read your TDEE. Your total daily energy expenditure appears instantly, and you can compare the Mifflin-St Jeor and Harris-Benedict results side by side. This figure is your maintenance level.
Adjust and explore. Change any input to see how it moves your number, for example how switching from lightly to moderately active changes the total. There is no submit button and no limit on recalculations.

Worked example one: comparing both formulas

Take a woman who is 30 years old, weighs 65 kilograms, stands 168 centimeters tall, and is moderately active. Using Mifflin-St Jeor, her BMR is 10 times 65 (650), plus 6.25 times 168 (1,050), minus 5 times 30 (150), minus 161, which comes to about 1,389 calories. Multiplying by the moderately active factor of 1.55 gives a TDEE of roughly 2,153 calories.

Now run the same person through the revised Harris-Benedict equation. Her BMR is 447.593, plus 9.247 times 65 (601.1), plus 3.098 times 168 (520.5), minus 4.330 times 30 (129.9), which totals about 1,439 calories. Multiplying by 1.55 gives a TDEE of roughly 2,231 calories.

The two methods land about 78 calories apart, at 2,153 and 2,231. Neither is the single correct answer, because both are estimates. What the comparison tells you is that her true maintenance is somewhere in that neighborhood, most likely a little over 2,100 calories, and that a difference smaller than a light snack is well within the expected margin. She would pick one figure, eat at it for a few weeks, and adjust from what the scale shows.

Worked example two: how activity level swings the number

Now take a man who is 35 years old, weighs 82 kilograms, and is 178 centimeters tall. His Mifflin-St Jeor BMR is 10 times 82 (820), plus 6.25 times 178 (1,112.5), minus 5 times 35 (175), plus 5, which is about 1,763 calories. That resting figure does not change, but his TDEE depends entirely on how active he is.

If he is sedentary, his TDEE is 1,763 times 1.2, about 2,115 calories. If he is moderately active, it is 1,763 times 1.55, about 2,732 calories. If he is very active, it is 1,763 times 1.725, about 3,040 calories. From the same body, the maintenance number ranges from roughly 2,115 to 3,040 depending only on the activity level chosen.

That spread of more than 900 calories is the clearest reason to be honest about your activity. Claiming very active when your week is mostly sedentary would set his maintenance nearly a thousand calories too high, and any plan built on it would misfire. When in doubt, choosing the lower level and letting real results correct it is the safer approach.

Worked example three: working in pounds and inches

Plenty of people use imperial units, so here is how that flows. Take a woman who is 45 years old, weighs 140 pounds, stands 5 feet 4 inches tall, and is lightly active. The tool converts 140 pounds to about 64 kilograms and 5 feet 4 inches (64 inches) to about 163 centimeters. If you ever need those conversions on their own, our unit converter handles them in a second.

Her Mifflin-St Jeor BMR is 10 times 64 (640), plus 6.25 times 163 (1,018.75), minus 5 times 45 (225), minus 161, which is about 1,273 calories. Applying the lightly active multiplier of 1.375 gives a TDEE of roughly 1,750 calories.

That 1,750 figure is her maintenance level. To see the components at work, about 1,273 of it is her resting BMR, roughly 175 calories is the thermic effect of a day's food at about 10 percent of intake, and the remainder is her everyday movement plus her light exercise. The tool does all the unit conversion and the multiplication for you, so you simply read the maintenance number and, if you like, the formula comparison beside it.

Using your TDEE to plan nutrition and training

Once you know your TDEE, the planning becomes straightforward, and we keep this part deliberately brief because the maintenance number is the star of this page. To hold your weight, aim to eat around your TDEE on average. To lose weight, eat below it, with a deficit of about 500 calories a day being a common, sustainable choice. To gain weight or support muscle growth, eat above it with a modest surplus. Those three moves cover almost every goal.

Your TDEE also guides training, not just eating. Knowing roughly how many calories you burn helps you fuel harder sessions and understand why a single workout rarely offsets a large meal, since exercise is often a smaller slice of TDEE than people assume. If muscle gain is the goal, most of the work is a small, consistent surplus plus resistance training and enough protein, rather than any single number on a screen.

For turning your maintenance figure into a specific daily target, with a suggested deficit or surplus already applied for your goal, our calorie calculator is the natural next step. It starts from the same energy expenditure logic and focuses on the goal side, while this TDEE calculator focuses on getting the maintenance number itself right. Used together, they cover both halves of the plan.

Tips and common mistakes

The single most common mistake is overstating your activity level. It is tempting to round up, but as the worked example showed, jumping one level too high can inflate your maintenance by hundreds of calories and quietly undo a deficit. Answer for a genuinely typical week, and when you are between two levels, choose the lower one.

A second mistake is treating the output as exact. Every TDEE calculator uses averages and cannot measure your real muscle mass, hormones, or the true size of your NEAT. Expect the number to be a good estimate with a margin of a few hundred calories, and plan to refine it. The reliable method is to eat at your estimated maintenance for two or three weeks, track your weight, and adjust: if you are gaining slowly, your real TDEE is a bit lower than the estimate, and if you are losing, it is a bit higher.

Other useful habits include weighing yourself under consistent conditions and watching the weekly trend rather than daily noise, recalculating after a meaningful weight change since a lighter body burns less, and not confusing BMR with TDEE when reading other tools. Finally, remember that the calculator's number is about energy quantity, not food quality. Protein, fiber, micronutrients, sleep, and consistency all shape results alongside the calorie total, and a maintenance figure is a framework rather than the whole picture.

Why two people with the same stats get different results

It can be puzzling that two people of identical weight, height, age, and sex can have genuinely different maintenance needs, yet a calculator gives them the same estimate. The reason lives mostly in the parts a formula cannot see. Body composition is a big one: muscle is more metabolically active than fat, so a lean, muscular person of a given weight tends to have a higher BMR than someone of the same weight with less muscle. The equations use only total weight, so they cannot tell the difference, though adding your body fat percentage in the tool switches it to the Katch-McArdle formula, which works from lean mass and closes part of that gap.

NEAT is another major source of variation. Some people are natural movers who pace, gesture, and fidget through the day, burning several hundred extra calories without a single formal workout, while others are far stiller. Genetics, hormones, certain medications, sleep, and even the temperature around you all shift energy expenditure too. This is not a flaw unique to one tool; it is the inherent limit of estimating a living, adapting metabolism from four numbers.

None of this makes a TDEE calculator unhelpful. It gives you a well grounded starting estimate, which is far better than a blind guess, and the two formula comparison makes the built in uncertainty visible. The way to close the gap between estimate and reality is simple: use the number to act, then let your own results over a few weeks fine tune it. Your body is the final authority, and the calculator is the informed first draft.

Your inputs stay on your device

Weight, height, age, and sex are personal, and many people would prefer not to hand them to a website that might store or share them. That is why we built the ToolFiddle TDEE calculator to run entirely in your browser. When you enter your stats, the BMR equations and the activity multiplication happen locally in JavaScript on your own device. Your numbers are not uploaded to a server, not saved in any database, and not logged for anyone to review.

This on-device design means there is no account holding your data, no hidden cookie recording your entries, and nothing left behind once you close the tab. Many free fitness calculators route everything you type through their servers, where it can be stored, profiled, or tied to advertising and email lists. We chose the opposite approach deliberately, because working out your energy expenditure is arithmetic that has no reason to leave your screen. If you are careful about where you put health information, this tool was designed with that care in mind.

Genuinely free, with no catches

Some energy expenditure calculators reveal a number and then push you to register, hand over an email for a plan, or subscribe before it will show the macro breakdown or the "accurate" version. The ToolFiddle TDEE calculator does none of that. There is no sign-up, no email, no account, and no daily limit, and nothing useful is locked away. You can calculate your own TDEE, then a friend's or family member's, as many times as you like in one sitting.

Every feature is open to everyone: metric and imperial units, the activity multipliers, and the comparison between the Mifflin-St Jeor and Harris-Benedict results. There is no premium tier fencing off part of the answer and no watermark on anything. We keep it free because a tool that runs on your device costs almost nothing to serve, and we would rather it help anyone who wants an honest maintenance number than trade that number for your contact details, which is how a fair few competing sites operate.

Instant, unlimited, and light to load

Since the calculation runs on your device, your TDEE appears immediately. There is nothing to upload, no queue behind other users, and no spinner while a remote server computes. The maintenance number updates live as you change an input, so you can watch how a different activity level or an extra few kilograms moves the figure, all without a page reload.

The page is also kept light. It is not weighed down by the stacks of ad scripts and trackers that slow many fitness sites, especially on a phone or a weak connection. A lean page loads quickly even on an older device and responds the instant you type. Quick, unlimited, and free of clutter is how a focused calculator should feel, particularly one you might reach for at the gym, in the kitchen, or while planning a training block.

Works on any device, even offline

The TDEE calculator runs in any modern browser on a phone, tablet, laptop, or desktop, across every major operating system, with nothing to install. The layout adapts to your screen, so entering your stats on a phone is as comfortable as on a large monitor.

Because all the math runs locally, the tool keeps working after you go offline. Once the page has loaded, you can switch to airplane mode, lose signal, or disconnect completely and still calculate your total daily energy expenditure. That makes it dependable while traveling, in a gym with poor reception, or anywhere the network is unreliable. You only need a connection to load the page at the start or to open other ToolFiddle tools.

Related ToolFiddle tools

If the TDEE calculator is useful to you, several other ToolFiddle tools work well alongside it. The calorie calculator takes your maintenance number and turns it into a daily target for losing, holding, or gaining weight, with the deficit or surplus already applied. The BMI calculator gives a quick body mass index from your height and weight. The unit converter switches between kilograms and pounds or centimeters and inches when your figures are in the other system, and the percentage calculator helps with things like tracking weight change as a percentage. Each runs on your device with the same privacy-first design.

Quick recap

A TDEE calculator estimates your total daily energy expenditure, the calories your body burns in a day, which is also your maintenance level. It finds your basal metabolic rate from weight, height, age, and sex using the Mifflin-St Jeor equation (or the older Harris-Benedict, for comparison), then multiplies by an activity factor from 1.2 for sedentary up to 1.9 for extremely active. Your TDEE is built from four parts: BMR, the thermic effect of food, NEAT, and exercise. Pick an activity level that matches your real week, expect the result to be a solid estimate with a margin of a few hundred calories, and refine it by tracking your weight over two or three weeks. To turn the maintenance number into a goal target, hand it to the calorie calculator. The ToolFiddle TDEE calculator computes it instantly, shows both formulas, stays free with no sign-up or limits, and keeps your inputs on your own device.

TDEE Calculator

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Works offline