Quick answer: two hours of cross-country hiking (Compendium code 17080, 6.0 METs) burns about 896 kcal for a 160 lb (72.6 kg) hiker, or 747 kcal net of resting. The same two hours with a daypack (17012, 7.8 METs) comes to about 1,165 kcal.
Two ways to estimate a hike
By activity. The 2024 Adult Compendium of Physical Activities assigns each activity a MET value: how many times resting energy use it takes. Pick the line that matches your outing, from slow ambling with no load (3.8 METs) up to brisk hill climbing with 20 lb or more on your back (10.0 METs). This is the quickest choice when you do not know your speed.
By speed and slope. If a watch or map gives you average speed and you know roughly how steep the trail was, switch the method to the ACSM walking equation. It handles grade directly, which suits steady climbs. The tile next to the result always shows the other method, so you can compare them.
Worked example
A MET is 3.5 ml of oxygen per kg per minute. For 72.6 kg at 6.0 METs: 6.0 x 3.5 x 72.6 / 1,000 = 1.52 litres of oxygen a minute, times 4.9 kcal per litre = 7.5 kcal a minute, or 896 kcal over 120 minutes. Put another way, each MET costs about 1.03 kcal per kg per hour with the 4.9 conversion. With the ACSM route, 2.5 mph (67 m/min) up a 10% grade gives an oxygen cost of 22.3 ml per kg per minute (about 6.4 METs) and about 951 kcal in two hours. The same walk on the flat would be about 436 kcal.
What these numbers leave out
- Compendium values describe typical adults doing that activity. Your pace inside a category may be faster or slower.
- Pack weight only counts through the activity you choose; the calculator does not add the pack to body weight.
- The ACSM equation covers walking uphill. Rough ground, scrambling, altitude, snow and long descents are not in it.
- Average grade on an up-and-back trail is near zero, yet the climb still costs energy. For those, the Compendium line is the safer pick.
- Read every figure as an estimate. Hiking burns energy, but this page makes no weight-loss promise.
For pavement walks, use the walking calorie calculator. Planning a trail run? Try the running calorie calculator and the grade-adjusted pace calculator.
Sources: Herrmann et al. (2024), 2024 Adult Compendium of Physical Activities, J Sport Health Sci; 2024 Adult Compendium: walking and hiking activities; ACSM's Guidelines for Exercise Testing and Prescription, Table 7.3 metabolic calculations (as reproduced by Texas Tech University). Rules checked . Found a problem? Tell us.
Questions
How many calories does hiking burn per hour?
For a 160 lb person, roughly 284 kcal an hour ambling with no load (3.8 METs), 448 kcal on a cross-country hike (6.0 METs) and 582 kcal with a daypack (7.8 METs).
Does carrying a backpack burn more calories?
The Compendium rates backpacking at 7.0 METs and hiking with a daypack at 7.8 METs, against 5.3 METs for hiking at a normal pace with no load. Hill climbing with 21 to 40 lb is 7.5 METs.
Is hiking better than walking for calories?
Usually it burns more per hour because of hills and rough ground. At 2.5 mph, a 10% grade more than doubles the burn compared with flat walking in the ACSM equation (about 951 against 436 kcal over two hours for a 160 lb hiker).
What is a MET?
A metabolic equivalent: 1 MET is the energy used sitting quietly, defined as 3.5 ml of oxygen per kg of body weight per minute. An activity at 6 METs uses six times that.