How many calories do you burn doing nothing?

Direct answer. “Doing nothing” means staying alive: breathing, pumping blood, repairing cells and running your brain. That costs most adults between 1,200 and 2,000 kcal a day. The exact figure is your basal metabolic rate, or BMR. It is not a bonus on top of exercise. It is the floor your whole day stands on.

What counts as “doing nothing”?

“Doing nothing” is not one number. Sleeping, lying awake, sitting at a desk and watching TV all cost slightly different amounts. Scientists split the idea into four terms, and mixing them up is the most common source of bad calorie advice.

Definitions follow the 2024 Adult Compendium of Physical Activities and the measurement methods described by Mifflin et al. (1990) and Byrne et al. (2005).

For the rest of this guide, “doing nothing” means awake, still and fasted — not asleep, not digesting a meal, not fidgeting. That is the cleanest definition of BMR. It is also the number most calculators try to predict.

How many calories do you burn doing nothing by body size?

Weight is the biggest single dial in the equation. In the Mifflin-St Jeor formula, every extra kilogram adds about 10 kcal per day to the estimate. Height and age adjust it. Sex changes the constant.

The table below uses the Mifflin-St Jeor equation for a 30-year-oldat 175 cm (men) and 163 cm (women). These are calculated estimates, not measurements.

Calculated with the Mifflin-St Jeor equation (Mifflin et al., 1990). Values are rounded. Your real burn can sit meaningfully above or below this line.

Read the table as a band, not a promise. A 70 kg adult can land 100 to 200 kcal either side of the estimate without anything being “wrong.” The next sections show why.

How do you calculate your resting burn in five steps?

The most widely validated bedside equation is Mifflin-St Jeor. It was derived from 498 healthy adults and predicts resting energy expenditure with an R² of 0.71 (Mifflin et al., 1990). Here is the whole method.

Men: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
Women: BMR = 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161

1. Convert weight to kilograms. Pounds ÷ 2.2046. A 154 lb adult is about 70 kg.
2. Convert height to centimetres. Feet × 30.48 plus inches × 2.54. Five foot nine is about 175 cm.
3. Pick the right constant. Add 5 for men, subtract 161 for women.
4. Do the arithmetic. For a 70 kg, 175 cm, 30-year-old man: 700 + 1,093.75 − 150 + 5 = 1,648.75, rounded to 1,649 kcal.
5. Compare with measured averages. The 1-MET shortcut would say 70 × 24 = 1,680 kcal. The difference is small here, but it grows at other body sizes.

Why the 1-calorie-per-kilo rule overestimates your burn

The 1-MET convention comes from one 70 kg, 40-year-old man. Researchers later measured 769 adults aged 18 to 74, weighing 35 to 186 kg. Their average resting oxygen use was 2.6 mL/kg/min — well below the assumed 3.5.

The calorie gap is smaller but still real. The 1 kcal/kg/hour convention overestimated resting energy expenditure by about 20% on average. For a 70 kg adult, that is 1,680 kcal from the shortcut versus roughly1,400 kcal from the measured average — a 280 kcaldifference in the estimate.

“...overestimates the actual resting VO₂ value on average by 35%.”

— Byrne NM, Hills AP, Hunter GR, Weinsier RL, Schutz Y, Journal of Applied Physiology, 2005

So use the equation, not the shortcut, when you want a resting number. Keep MET tables for what they do well: comparing activities against each other. Ourguide to MET valuesexplains that side of the math.

What actually changes your resting burn?

Fat-free mass is the strongest known contributor. In a study of 150 white adults in northeast Scotland, researchers split the variance in BMR into measurable parts. The results are unusually clear.

Source: Johnstone et al., 2005, American Journal of Clinical Nutrition(N = 150). Percentages describe between-subject variation, not an individual’s metabolism.

“63% was explained by FFM, 6% by FM, and 2% by age.”

— Johnstone AM et al., American Journal of Clinical Nutrition, 2005

Sex matters inside the equation, but not as an independent factor in that study. The formula uses different constants because average body composition differs. Age also gets a steady penalty: about 5 kcal per year, or 50 kcal per decade, for the same body size.

That age penalty is not the whole story. A 2021 Science analysis of doubly-labelled-water data, spanning ages 8 days to 95 years, found that fat-free-mass-adjusted total energy expenditurestays stable from age 20 to 60 and only declines afterwards. Your BMR may drift down while your total daily burn holds steady, because movement and other components shift.

Do you burn calories while you sleep?

Yes. Sleeping is the closest thing to true “doing nothing,” and it still costs energy. The Compendium assigns sleep about 1.0 MET — the baseline itself.

For a 70 kg adult, eight hours of sleep works out to about560 kcal on the MET scale. The Mifflin equation gives a similar number: 1,649 ÷ 24 × 8 ≈ 550 kcal. Apply the measured-rest correction from Byrne et al. and the realistic figure drops toward450–470 kcal.

MET values from the Compendium. These are total energy costs for the time block, not additional calories on top of BMR.

The practical point: sleep is not a bonus burn. It replaces sitting time. Swapping an hour of TV for an hour of sleep changes the total only slightly. Swapping an hour of sitting for an hour of standing or walking changes it much more.

Sitting, standing and TV: what does a day cost?

Daily posture is where “doing nothing” starts to blur into real activity. The Compendium separates sleep (1.0 MET), seated screen time (1.3) and general standing (1.8). The differences look small per hour. Across a full day, they are not.

Levine and colleagues tracked 10 lean and 10 mildly obese sedentary volunteers every half-second for 10 days. The obese participants were seated about2 hours longer per day. The researchers estimated that adopting the lean group’s movement habits could add around 350 kcal per day.

“...seated, on average, 2 hours longer per day than lean individuals.”

— Levine JA et al., Science, 2005 (N = 20)

This is also where most online advice goes wrong. People add their exercise calories to their BMR and call it a day. That double-counts. A MET-based estimate for a 30-minute walk already includes the resting cost of those 30 minutes.

The cleaner model is a ladder:

1. BMR — the floor. About 1,200–2,000 kcal for most adults.
2. Digestion — diet-induced thermogenesis adds 5–15% of daily energy expenditure on a mixed diet (Westerterp, 2004).
3. Daily movement — posture, chores, commuting and fidgeting.
4. Planned exercise — the smallest slice for most people, not the largest.

If you want a total, start with BMR and apply an activity factor. Ourdaily calorie calculator does exactly that with TDEE. If you want a single activity’s cost, use thecalories burned calculator. Do not add the two together.

How accurate is a resting-burn calculator?

Accurate enough to plan with. Not accurate enough to treat as a measurement. Three findings set the honest range.

• The equation explains 71% of the variance in the 498 adults used to build it (Mifflin et al., 1990). That leaves 29% for everything else.
• Older equations run high. Harris-Benedict, published in 1919, overestimated measured resting expenditure by 5% in the Mifflin validation sample.
• Real people vary more than equations admit. The measured-rest correction is about 20% for calories and 35% for oxygen use (Byrne et al., 2005). Another study left 26% of BMR variation unexplained (Johnstone et al., 2005).

Indirect calorimetry is the reference method: you breathe into a machine that measures oxygen use and carbon-dioxide production. It is used in clinics and research. It is not needed for most people setting a calorie target.

See a clinician if your weight changes sharply without explanation, if you have a thyroid condition, or if you are considering a very low-calorie diet. Those are medical questions, not calculator questions.

Case study: three people, one idle day

To make the range concrete, here are three calculated profiles. Each spends the day doing nothing beyond normal sedentary life. The estimate uses Mifflin-St Jeor for BMR and a 1.2 activity factor for a desk-bound TDEE.

Illustrative calculations, not measurements. Sedentary TDEE = BMR × 1.2.

The spread between the smallest and largest profile is about 520 kcal a day at rest. None of them is “broken.” They are different bodies. This is also why copying someone else’s calorie target rarely works.

Now add movement. The woman’s sedentary day is 1,540 kcal. A 30-minute brisk walk at MET 4.3 adds roughly 151 kcal on the MET scale — but remember that this replaces resting time, so the net gain is smaller than 151. The lesson is not to chase the biggest number. It is to build a consistent week.

Can you change how many calories you burn doing nothing?

Modestly. Your BMR is not a fixed destiny, but it is not a dial you can crank with a pill either. The evidence supports four levers.

1. Maintain fat-free mass. It explains 63% of BMR variation. Strength work and adequate protein help you keep it, especially during weight loss.
2. Move more across the day. The NEAT gap in Levine’s study was worth about 350 kcal per day. Standing, walking meetings and chores count.
3. Eat enough protein. Diet-induced thermogenesis is higher on a high-protein diet: 14.6% versus 10.5% of energy intake in one small 1999 trial. The effect stays within the 5–15% band.
4. Sleep and recover. We include this as a general health lever, not a proven BMR booster. Our sources do not establish a direct resting-burn effect.

What does not work: “metabolism booster” foods and supplements. We found no source in this review showing a permanent BMR increase from either. Be sceptical of any claim that promises one.

What is changing in 2026–2027?

The three points below are our editorial forecast. They are not sourced findings.

• Population-specific equations. Expect more variants for older adults, pregnancy and specific clinical groups, instead of one adult formula.
• Device-based estimates. Wearables will keep blending heart rate, motion and body-composition data. Accuracy claims will need independent testing.
• Better “idle day” breakdowns. Tools will separate sleep, sitting and standing instead of showing one flat BMR number.

Your 7-day resting-burn plan

You do not need a lab. You need a baseline, a week of data and one honest adjustment. Here is the sequence.

1. Day 1 (5 min): calculate your BMR with the tool above. Write down the number.
2. Day 2 (5 min): open the daily calorie calculator and note your sedentary TDEE.
3. Day 3 (2 min): log your sleep hours and screen time. These are your two biggest “idle” blocks.
4. Day 4: add one 10-minute walk after a meal. Do not add the calories to your BMR; just note the habit.
5. Day 5: include a protein source at each main meal. Keep the change small enough to repeat.
6. Day 6: swap one seated block for standing or walking. Ten minutes is enough.
7. Day 7 (5 min): review. Compare your weight trend and energy levels with the estimate. Adjust after two to four weeks, not one day.

Keep two numbers: your BMR (the floor) and your TDEE (the daily budget). Everything else is detail. If you want the activity side, browse theactivity directory or readhow the calculator works.

Sources and further reading

1. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. “A new predictive equation for resting energy expenditure in healthy individuals.”American Journal of Clinical Nutrition. 1990;51(2):241–247.Open the DOI.
2. Byrne NM, Hills AP, Hunter GR, Weinsier RL, Schutz Y. “Metabolic equivalent: one size does not fit all.” Journal of Applied Physiology. 2005;99(3):1112–1119.Open the DOI.
3. Johnstone AM, Murison SD, Duncan JS, Rance KA, Speakman JR. “Factors influencing variation in basal metabolic rate include fat-free mass, fat mass, age, and circulating thyroxine but not sex, circulating leptin, or triiodothyronine.”American Journal of Clinical Nutrition. 2005;82(5):941–948.Open the DOI.
4. Levine JA, Lanningham-Foster LM, McCrady SK, et al. “Interindividual variation in posture allocation: possible role in human obesity.” Science. 2005;307(5709):584–586.Open the DOI.
5. Pontzer H, Yamada Y, Sagayama H, et al. “Daily energy expenditure through the human life course.” Science. 2021;373(6556):808–812.Open the DOI.
6. Westerterp KR. “Diet induced thermogenesis.” Nutrition & Metabolism. 2004;1:5.Open the DOI.
7. Westerterp KR, Wilson SA, Rolland V. “Diet induced thermogenesis measured over 24h in a respiration chamber: effect of diet composition.” International Journal of Obesity. 1999;23(3):287–292.Open the DOI.
8. Herrmann SD, Willis EA, Ainsworth BE, et al. “2024 Adult Compendium of Physical Activities: A third update of the energy costs of human activities.”Journal of Sport and Health Science. 2024;13(1):6–12.Read the open-access study.

Related guides on this site

• What is a MET and why does it decide your calorie burn? — the multiplier behind every activity estimate.
• Daily calorie calculator — BMR, TDEE and weight-loss targets.
• How the calories burned calculator works — the formula and its limits.
• Sleeping calories — MET 1.0, chart and calculator.
• Sitting calories — what a desk day costs.
• Watching TV calories — the easiest block to replace.
• Standing calories — the cheap upgrade from sitting.
• Frequently asked questions — quick answers on methods and accuracy.

Fact-check table

Every number in this guide traces to a named source or to arithmetic shown in the text. Calculated values are labelled as calculations.

Medical disclaimer

This guide provides general educational estimates only. It is not medical advice, diagnosis or treatment. Resting metabolism varies with body composition, thyroid function, medication, pregnancy and health conditions. Do not set a very low calorie intake or change a treatment plan based on these numbers. Speak with a doctor or registered dietitian before making significant changes. If you experience unexplained weight loss, persistent fatigue or other symptoms, seek medical care.

Who we are / what we are not: the Exercise Calorie Calculator editorial team builds transparent, source-linked estimators. We are not doctors, dietitians or a clinical lab. We publish our formula and our limits so you can check the work. Corrections:hello@exercisecaloriecalculator.com.