TDEE Calorie Calculator

Every day your body burns a certain number of calories just by being alive, and then burns more through everything you do on top of that. The grand total is called your TDEE, short for total daily energy expenditure, and it is the single most useful number in all of weight management. Eat more calories than your TDEE and you gain weight. Eat fewer and you lose weight. Eat almost exactly your TDEE and your weight stays stable. The TDEE Calorie Calculator on this page estimates that number for you in seconds, using only three simple inputs: your weight, your height, and your age.

Most people guess their calorie needs, and most people guess wrong. Some follow a generic 2,000-calorie rule that was never designed for their body. Others copy a meal plan built for someone taller, heavier, younger, or far more active than they are. A personalised estimate changes the game because your calorie needs are genuinely personal. A 90 kg man who works construction does not burn anything like a 55 kg woman who works at a desk, and a calculator that accounts for weight, height, and age captures most of that difference. Below you will learn what TDEE really means, how the estimate is built from a trusted scientific formula, and how to turn the three numbers this tool gives you into a practical eating plan.

What Is TDEE and Why Does It Matter?

TDEE stands for total daily energy expenditure. It is the total number of calories your body uses in a 24-hour period, and it is made up of four parts. The largest part is your basal metabolic rate (BMR), the energy needed to keep you alive at complete rest: your heart beating, your lungs breathing, your brain running, and your body temperature maintained. For most adults, BMR accounts for roughly 60 to 70 percent of TDEE. The second part is the thermic effect of food, the energy your body spends digesting what you eat, worth about 10 percent of your intake. The third part is exercise activity, the calories you deliberately burn through workouts and sport. The fourth is NEAT, non-exercise activity thermogenesis, which covers everything else: walking to the bus, fidgeting, typing, cleaning the house, and all the small movements of daily life.

TDEE matters because it is the anchor point of energy balance, the simple physics that governs body weight. When the calories you eat match your TDEE, your weight holds steady. When you eat less than your TDEE, your body makes up the shortfall from stored fat, and you lose weight. When you eat more, the surplus is stored, and you gain weight. Every successful diet in history, whatever its branding, works by moving one side of this equation. Knowing your TDEE therefore turns weight loss from guesswork into arithmetic. Instead of wondering whether 1,800 calories a day is too much or too little, you can compare it against your own estimated expenditure and see exactly where you stand.

BMR: The Engine Underneath Your TDEE

Before this tool can estimate your TDEE, it first estimates your BMR, and understanding BMR helps you read your results with confidence. Your basal metabolic rate is the number of calories you would burn in a day if you lay in bed doing absolutely nothing. It is driven mostly by the size of your body: more tissue, especially muscle, costs more energy to maintain. That is why weight and height are the two biggest inputs. A taller, heavier person has more cells to keep alive, so their BMR is higher. Age works in the opposite direction. As the years pass, people typically lose a little muscle mass and their metabolism slows, so BMR drifts downward by a few percent per decade after early adulthood.

This calculator estimates BMR with a widely respected formula called the Mifflin-St Jeor equation, which researchers consider one of the most accurate prediction formulas available. The classic equation has slightly different versions for men and women, because men on average carry more muscle at the same weight. This tool uses a gender-neutral version of the formula, which averages the two, so it works as a fair middle estimate for everyone. The formula is: BMR = 10 × weight in kilograms + 6.25 × height in centimetres − 5 × age in years − 78. That final constant of 78 is the midpoint between the male version, which adds 5, and the female version, which subtracts 161. The result is your estimated daily burn at complete rest, and it becomes the foundation on which the two TDEE figures are built.

How to Use the TDEE Calorie Calculator

Using the calculator takes less than a minute. There are three boxes to fill in, and then a single button to press.

1. Enter your weight in kilograms. Use your current morning weight, measured after using the bathroom and before eating, for the most consistent figure. The calculator accepts weights between 20 and 300 kg.
2. Enter your height in centimetres. Stand straight against a wall and measure if you are unsure; many people overestimate their height by a couple of centimetres. Valid entries run from 100 to 250 cm.
3. Enter your age in whole years. Your age nudges the estimate downward slightly, reflecting the natural metabolic slowdown with time. Ages from 10 to 100 are accepted.
4. Press Calculate. Three results appear instantly: your estimated BMR, your estimated daily calories at a sedentary activity level, and your estimated daily calories at an active level.

If you enter a value outside the sensible ranges, the calculator will ask you to correct it rather than produce a nonsense answer. The Reset button clears everything so you can run a fresh estimate, which is handy if you want to compare numbers for different weights, for example your current weight versus your goal weight, to see how your calorie needs will change as you slim down.

Worked Example 1: A 30-Year-Old at 70 kg and 175 cm

Let us walk through a complete example so you can see exactly how the numbers are produced. Meet our first example: a 30-year-old who weighs 70 kilograms and stands 175 centimetres tall. We enter 70 into the weight box, 175 into the height box, and 30 into the age box, then press Calculate.

First the tool computes BMR with the gender-neutral Mifflin-St Jeor formula: 10 × 70 = 700, plus 6.25 × 175 = 1,093.75, minus 5 × 30 = 150, minus the constant 78. Adding it up: 700 + 1,093.75 − 150 − 78 = 1,565.625, which rounds to 1,566 kcal/day. That is the estimated cost of keeping this body alive at total rest.

Next the tool scales BMR up to TDEE using two activity multipliers. For a sedentary lifestyle, someone who sits most of the day with little exercise, the multiplier is 1.2: 1,565.625 × 1.2 = 1,878.75, shown as 1,879 kcal/day. For an active lifestyle, with regular exercise or a physical job, the multiplier is 1.55: 1,565.625 × 1.55 = 2,426.72, shown as 2,427 kcal/day. So this person maintains weight on roughly 1,879 calories if sedentary or about 2,427 calories if active, a gap of nearly 550 calories that shows just how much movement matters.

Worked Example 2: A 45-Year-Old at 85 kg and 180 cm

Our second example is a 45-year-old weighing 85 kilograms at a height of 180 centimetres. Enter 85, 180, and 45, then press Calculate, and the tool runs the same formula. BMR comes out as 10 × 85 = 850, plus 6.25 × 180 = 1,125, minus 5 × 45 = 225, minus 78. That gives 850 + 1,125 − 225 − 78 = 1,672, displayed as 1,672 kcal/day. Notice that despite being heavier and taller than the first example, which pushes BMR up, the extra fifteen years of age pull it back down, leaving a BMR only about 100 calories higher.

The two TDEE figures follow. Sedentary: 1,672 × 1.2 = 2,006.4, shown as 2,006 kcal/day. Active: 1,672 × 1.55 = 2,591.6, shown as 2,592 kcal/day. If this person wanted to lose weight at a steady, sustainable pace, a common approach would be to eat about 500 calories below TDEE, which points to roughly 1,500 calories a day at a sedentary level or about 2,100 at an active level. Both examples show the same lesson: small differences in weight, height, and age compound into meaningfully different calorie targets, which is exactly why a personalised estimate beats a one-size-fits-all number.

Understanding the Activity Multipliers

The two TDEE outputs on this calculator come from multiplying your BMR by an activity factor, a simple number that represents how much you move. Researchers developed these factors by comparing the total daily burn of groups of people at different activity levels against their resting burn. The sedentary factor of 1.2 describes someone with a desk job and little deliberate exercise: their total burn is only about 20 percent above resting. The active factor of 1.55 describes someone who exercises moderately most days or has a fairly physical daily routine: their total burn runs about 55 percent above resting.

Choosing honestly between the two is important, and most people overestimate their activity. A useful rule of thumb: if you sit for most of the day and exercise fewer than three times a week, use the sedentary figure. If you train three to five times a week, walk a lot, or work on your feet, the active figure is closer to the truth. Very hard training athletes and manual labourers may burn even more, beyond 1.55, but for the great majority of people one of these two figures is the right anchor. When in doubt, start with the lower number. It is far easier to add calories later when the scale shows you are losing faster than planned than to undo weeks of frustration caused by starting too high.

Using Your TDEE for Weight Loss or Weight Gain

Once you know your TDEE, the path to a goal becomes refreshingly concrete. For weight loss, the standard sustainable target is a deficit of about 500 calories per day below TDEE, which typically produces a loss of around half a kilogram per week. Smaller deficits of 250 calories work too, just more slowly, and they are easier to live with. Very large deficits tend to backfire: hunger becomes intense, energy crashes, workouts suffer, and muscle is lost alongside fat. A good rule is to keep your intake at or above your BMR whenever possible and let activity contribute part of the deficit.

For weight gain, usually the goal is muscle rather than fat, the mirror image applies: eat roughly 250 to 500 calories above TDEE, with plenty of protein and progressive strength training so the surplus builds muscle instead of just padding. For maintenance, simply eat at TDEE and let your weight settle. Whichever goal you choose, treat the calculator’s number as a starting hypothesis. Track your weight trend over two to three weeks, compare it with what you expected, and adjust your intake up or down by a couple of hundred calories. Bodies adapt, water weight fluctuates, and no formula knows your life as well as your own data does.

Tips for Getting the Most Accurate Estimate

1. Weigh yourself consistently. Morning weight, after the bathroom and before food, measured the same way each time, gives the cleanest input.
2. Measure your height properly. Stand barefoot against a wall and mark it; guessing often adds phantom centimetres that inflate your BMR.
3. Be honest about activity. Most people land closer to sedentary than they think. Start with the lower TDEE if you are unsure.
4. Treat the result as a starting point. Follow it for two to three weeks, watch your weight trend, then adjust by 200 to 300 calories based on real results.
5. Recalculate after big changes. Every 5 kg of weight change shifts your TDEE noticeably, so rerun the numbers as your body changes.
6. Do not eat far below BMR. Very low intakes are hard to sustain and risk muscle loss, fatigue, and nutrient gaps; keep deficits moderate.
7. Count NEAT, not just workouts. Daily walking and general movement often matter more than gym sessions for total burn, so build more steps into ordinary days.
8. Remember it is gender-neutral. This tool averages the male and female formulas, so very muscular or very slight builds may sit a little above or below the estimate.

Frequently Asked Questions

1. What does TDEE actually mean?

TDEE stands for total daily energy expenditure: the total number of calories your body burns in a full day. It includes your resting metabolism, the energy used to digest food, deliberate exercise, and all the small movements of daily life. It is the number your calorie intake is compared against when planning weight loss, gain, or maintenance.

2. How is TDEE different from BMR?

BMR, or basal metabolic rate, is only the resting portion: what you would burn lying still all day. TDEE is BMR plus everything else, so it is always higher. This calculator shows you both, with BMR as the first result and TDEE at two activity levels as the second and third.

3. Which formula does this calculator use?

It uses the Mifflin-St Jeor equation, one of the most validated formulas for estimating resting metabolic rate. Because the classic equation differs by sex, this tool uses a gender-neutral version that averages the two, giving a fair middle estimate for everyone.

4. What do the 1.2 and 1.55 multipliers mean?

They are activity factors from nutrition research. Multiplying BMR by 1.2 estimates the burn of a sedentary person, while 1.55 estimates the burn of a moderately active person. Your true TDEE falls somewhere around these figures depending on how much you actually move each day.

5. How accurate is the estimate?

For most people it lands within about 10 percent of the true value, which is close enough to plan around. Individual metabolism, muscle mass, and daily habits cause variation, so treat the number as a starting point and fine-tune it against your real weight trend over a few weeks.

6. I am very muscular. Will the calculator underestimate me?

Possibly, by a modest amount. Muscle burns more calories at rest than fat does, and the formula only sees total weight, not body composition. Very muscular people may burn somewhat more than estimated, while people with very low muscle mass may burn a little less.

7. How many calories should I eat to lose weight?

A widely recommended approach is to eat about 500 calories below your TDEE each day, which typically leads to around half a kilogram of fat loss per week. Keep your intake at or above your BMR when possible, and adjust based on how your weight actually responds.

8. How many calories should I eat to gain weight?

Aim for roughly 250 to 500 calories above your TDEE, paired with strength training and enough protein so the extra weight becomes muscle rather than fat. Gaining faster than about half a kilogram a week usually adds more fat than muscle.

9. Should I use the sedentary or the active number?

Use the sedentary figure if you sit most of the day and exercise fewer than three times weekly. Use the active figure if you train several times a week or spend much of the day on your feet. When uncertain, start with the lower number and adjust upward if you lose weight faster than intended.

10. Why does age lower the estimate?

Metabolism tends to slow with age, partly because people gradually lose muscle mass. The formula subtracts a small amount per year of age to reflect this. Staying active and doing resistance training are the best ways to fight the slowdown.

11. Do I need to enter my gender?

No. This calculator deliberately uses a gender-neutral version of the formula, so it works for everyone without that input. The trade-off is a slightly wider margin of error at the extremes of body composition.

12. How often should I recalculate my TDEE?

Recalculate whenever your weight changes by about 5 kg, or every couple of months during an active weight-loss or weight-gain phase. A smaller body burns fewer calories, so old targets gradually become outdated.

13. Can I use this calculator while pregnant or breastfeeding?

The formula was not designed for pregnancy or lactation, both of which change energy needs substantially. Use it only as a rough reference and follow guidance from your doctor or a registered dietitian for those stages of life.

14. Does the calculator account for medical conditions?

No. Thyroid disorders, certain medications, and other medical factors can raise or lower metabolism beyond what weight, height, and age predict. If you have a relevant condition, treat the estimate cautiously and discuss targets with a healthcare professional.

15. Is it safe to eat below my BMR?

Occasionally dipping slightly below is not dangerous for most healthy adults, but living far below BMR long-term risks fatigue, muscle loss, hormonal disruption, and nutrient deficiencies. Moderate deficits built on a foundation at or above BMR are safer and more sustainable.

CONCLUSION

Your TDEE is the number that turns eating from guesswork into a plan. This calculator estimates it from your weight, height, and age using the trusted Mifflin-St Jeor formula, then shows you what that means at a sedentary and an active lifestyle, with your BMR alongside for context. Use the numbers as your starting point, compare your intake against them, and let two or three weeks of real-world results fine-tune the target. Whether your goal is losing fat, building muscle, or simply holding steady, everything gets easier once you know roughly how much fuel your body actually burns each day.