How Many Calories Does Sex Burn?

How many calories sex burns varies a lot, but the average is about 85 kcal for a session of roughly 25 minutes, from a 2013 study that measured it in couples’ own homes. Men averaged 101 kcal and women 69 kcal. A single session ran from about 12 kcal to over 300, so the average describes nobody in particular.

How many calories does sex burn on average?

About 85 kcal for a session of 24.7 minutes, according to the study’s data. It followed 21 heterosexual couples aged 19 to 31 who wore an armband that estimates energy use. Each couple did four sessions at home over a month, with no drugs or alcohol, and the armband went on right before and came off right after. Here is the study’s own table, with the last column from its text.

	Men	Women	Both
Energy per session	101 kcal	69 kcal	85 kcal
Energy per minute	4.2 kcal	3.1 kcal	3.6 kcal
Intensity	6.0 METs	5.6 METs	5.8 METs
30-minute treadmill session, same people	276 kcal	213 kcal	245 kcal

A MET is the energy you use sitting still, about 1 kcal per kg of body weight per hour, so 6.0 METs is six times resting. The authors call that moderate intensity. It also lasted less time than the treadmill session. Over the whole session, sex came to about 38% of the treadmill’s energy. That makes it a real expense, though not a big one. Resting is the cheap end of the scale, and how many calories you burn sleeping sets the floor.

The spread is wide: 13 to 306 kcal per session for men, 12 to 164 for women, and 10 to 57 minutes in length.

One pattern surprised me. Men averaged 118 kcal in their first session and 98, 94 and 90 in the next three. Women went 83, 69, 55 and 65. The authors report that the third session was significantly lower than the first for both sexes. They don’t say why, so I won’t guess.

The sample was narrow: young, healthy, active volunteers from Montreal in relationships of 6 to 24 months, told to do what they usually do. The authors say the results are limited to that group, so if you are older or heavier, or have been together for years, your number may sit elsewhere. The couples’ own guesses landed close to the armband, with men guessing 100 kcal and women 76.

A popular claim puts a session at 100 to 300 kcal. The authors note that no scientific data had documented it, and their measured average sits below the bottom of that range.

Does sex count as exercise, and what if a session is longer?

By intensity it can. By total energy it falls short of a treadmill session. The 2024 Adult Compendium of Physical Activities rates sexual activity at 5.8 METs for vigorous effort, 3.0 for general moderate effort and 1.8 for passive, light effort such as kissing and hugging. The Compendium’s authors class 3.0 to 5.9 METs as moderate and 6.0 or more as vigorous, so the average session falls in the moderate band.

The study found the same thing: intensity averaged 71% of the treadmill’s, while energy per minute averaged 47%.

For a different length, multiply the minutes by the study’s rate of 3.6 kcal per minute. Ten minutes comes to 36 kcal, 45 minutes to 162 kcal and 57 minutes, the longest session, to about 205 kcal. Those sums are mine, and they assume steady effort. Read them as a guide.

The Compendium’s own formula, METs × kg × hours, tells a different story. For a 70 kg (154 lb) person over 25 minutes (0.417 h), it gives 3.0 × 70 × 0.417 = 88 kcal at the moderate rate and 5.8 × 70 × 0.417 = 169 kcal at the vigorous rate. The measured average matches the first number and falls well under the second. I trust the measured sessions more, though an armband is still an estimate.

Should you count it in your day?

No. Leave it out of your log. The cost is small next to the total in how many calories you burn a day, and no single number is firm enough to plan food around. A wrist device would not do better. In a Stanford test of seven wrist devices, median energy errors ran from 27.4% to 92.6%, so a watch’s figure for one session is as rough as the table’s.

If you have a heart condition, or a doctor has told you to limit exertion, ask what level of activity suits you. This page can’t answer that. For the effort of a lifting session, see how many calories weight lifting burns, and for a target, how many calories you should burn a day. If a walk is the thing you want to measure, the steps to calories calculator uses the same Compendium METs for walking.

Keep the 85 kcal for conversation. A food plan needs a steadier number than that.