Calories Burned from Sleeping:
Table of Contents
How sleeping calorie burn is calculated
Sleeping is assigned a MET value of 0.95 in the Compendium of Physical Activities. A MET expresses energy cost as a multiple of resting metabolism: 1 MET is what you burn sitting quietly. Sleeping at 0.95 MET is essentially basal metabolism with a 5% reduction for the lower muscle tone and slightly reduced thermoregulation of sleep.
Calories = MET × Weight (kg) × Duration (hours)
For comparison with related low-MET states:
| State | MET | Notes |
|---|---|---|
| Sleeping | 0.95 | Slightly below resting; averaged across REM and NREM stages |
| Lying quietly awake | 1.0 | The reference resting state |
| Sitting quietly | 1.3 | What 1 MET technically should be; the Compendium lists 1.3 due to upright posture |
| Standing quietly | 1.3 | About the same as sitting, despite common claims to the contrary |
| Light walking (2 mph) | 2.8 | For context — roughly 3x the burn of sleeping |
Worked example with the calculator defaults
The calculator opens with a 74 kg adult sleeping for 8 hours:
- Calories = 0.95 × 74 × 8 = 563 calories.
- Per hour: 0.95 × 74 = 70 calories.
That number is basically the person's BMR pro-rated to 8 hours. If you used the BMR calculator for a 74 kg, 30-year-old male of average height, it would give a daily BMR around 1,700 calories — 8 hours' worth of which is roughly 570. Same answer through two different formulas.
Calories burned sleeping by body weight
| Body weight | Per hour | 6 hours | 8 hours | 9 hours |
|---|---|---|---|---|
| 60 kg (132 lb) | 57 cal | 342 cal | 456 cal | 513 cal |
| 75 kg (165 lb) | 71 cal | 428 cal | 570 cal | 641 cal |
| 90 kg (198 lb) | 86 cal | 513 cal | 684 cal | 770 cal |
Two practical observations from this table:
- Extra sleep doesn't burn meaningfully extra calories. The difference between 6 and 9 hours for a 75 kg person is about 213 calories — smaller than the calories in a single beer.
- The total is non-trivial over a year. 570 calories a night for 365 nights is 208,000 calories — roughly 60 pounds of "fat equivalent" sustained by basal metabolism alone. That's not weight you'll lose, but it shows how dominant BMR is in total daily energy expenditure.
Limitations — and what the calculator can't tell you
The honest framing for sleep calorie burn:
- You can't meaningfully change this number. Unlike exercise where intensity and duration give you real levers, sleep calorie burn is essentially fixed by your body mass. Reading articles about "hacks to burn more calories in your sleep" is mostly a waste of time.
- The MET shortcut ignores age, height, and sex. Two 75 kg adults — a 25-year-old male at 185 cm and a 65-year-old female at 160 cm — have different BMRs (the male's is roughly 20% higher) but the same MET-based sleep calorie estimate. The BMR calculator uses Mifflin-St Jeor and is more accurate for individualized numbers.
- Sleep matters for weight loss, but not because of calories burned during sleep. Short sleep raises hunger hormones, drops insulin sensitivity, reduces willpower, and increases late-night eating. Multiple studies show people sleeping under 6 hours eat 200–400 more calories per day. The lever is the waking-hour appetite effect, not the in-bed burn.
- "Burning calories while you sleep" is the wrong frame for weight loss. The interesting question isn't how many calories you burn at night — it's whether your TDEE (total daily energy expenditure) is greater than your intake over a 24-hour cycle. Use the daily calorie calculator for that.
- Sleep stage variation is real but averages out. Deep sleep dips below 0.85 MET; REM rises to roughly 1.0 MET. Across a full night the 0.95 average holds up.
The blunt summary: yes, you burn about 50–90 calories an hour sleeping. No, you can't optimize this number. Prioritize sleep for its effects on hormones, recovery, and daytime hunger — those are the levers that actually move body composition.
Sources & references
- Compendium of Physical Activities — Ainsworth BE et al. (2011). "2011 Compendium of Physical Activities: a second update of codes and MET values." Medicine & Science in Sports & Exercise 43(8): 1575–1581. Lists sleeping at 0.95 MET.
- St-Onge MP et al. (2011). "Short sleep duration increases energy intakes but does not change energy expenditure in normal-weight individuals." American Journal of Clinical Nutrition 94(2): 410–416 — landmark study on how sleep restriction raises caloric intake.
- Spaeth AM et al. (2013). "Effects of experimental sleep restriction on weight gain, caloric intake, and meal timing in healthy adults." Sleep 36(7): 981–990.
- Harvard Health Publishing — How much sleep do we really need?
- American College of Sports Medicine — ACSM's Guidelines for Exercise Testing and Prescription.
FAQs
Sleeping is rated 0.95 MET in the Compendium of Physical Activities — almost identical to lying quietly awake. For a 75 kg (165 lb) adult that's about 71 calories per hour, or 570 calories over an 8-hour night. A 60 kg person burns roughly 57 cal/hr; a 90 kg person about 86 cal/hr. The number is basically your basal metabolic rate (BMR) expressed in hourly form.
Not directly — the calorie burn during sleep is barely below your waking resting rate. But sleep duration does affect weight loss through other channels. Sleep deprivation reliably increases hunger hormones (ghrelin), decreases satiety hormones (leptin), reduces insulin sensitivity, and impairs the willpower needed to maintain a deficit. Adults sleeping fewer than 6 hours have been shown in multiple studies to eat around 300 extra calories per day. So "sleep more to lose weight" works, just not because of what you burn while asleep.
REM sleep is slightly more metabolically active — oxygen consumption rises about 5–10% above non-REM stages, mostly from brain activity. Deep sleep (NREM stage 3) is the lowest-burn phase, sometimes dipping below 0.85 MET. Over a full night the difference averages out, which is why the calculator uses a single 0.95 MET value rather than modeling sleep stages.
Yes, almost exactly. 1 MET is defined as 1 kcal per kg of body weight per hour, which closely approximates resting metabolic rate. Sleeping at 0.95 MET is 95% of that. For accurate daily energy expenditure, use a dedicated BMR calculator that incorporates age, height, and sex via the Mifflin-St Jeor equation — it will give a more individualized number than the MET shortcut used here.
Fitness trackers typically estimate sleep calories from your personalized BMR (calculated from age, height, weight, and sex) rather than a flat MET value. For most adults that produces a number within 10–15% of this calculator's output, but trackers can differ from each other by 30% or more. Treat both as estimates — the true value can only be measured by indirect calorimetry in a lab.