About the Rucking Calorie Calculator
Rucking — walking with a loaded backpack or weighted vest — burns noticeably more energy than walking unloaded, but generic calorie counters ignore the pack. This calculator uses the Pandolf equation, developed by US Army researchers to predict the metabolic cost of soldiers carrying loads, so it accounts for your body weight, the pack weight, walking speed, uphill grade and the terrain underfoot.
Enter your details to see calories for the session and per hour, the metabolic rate in watts, and how many of those calories the pack itself added. The chart shows how the burn changes as you add weight, which is handy when deciding whether to carry more or walk faster.
The equation is designed for walking speeds (roughly 2.5–7 km/h) and level or uphill ground. It was not built for running or descents, where it tends to over- or under-estimate, so use a flat or uphill grade and a walking pace for the most realistic result.
With the default inputs, the calories burned is 395 kcal. Change any value above to recalculate instantly.
How to use the rucking calorie calculator
- 1Choose metric or imperial units.
- 2Enter your body weight and the weight of your pack or vest.
- 3Enter your walking speed and how long you rucked.
- 4Add the average uphill grade and pick the terrain.
- 5Read total calories, calories per hour and the extra burn from the pack.
Formula and method
The Pandolf equation (Pandolf, Givoni and Goldman, 1977) predicts metabolic rate in watts. The first term is the cost of standing, the second the extra cost of supporting a load, and the third the cost of moving body plus load at speed V up a grade G, scaled by a terrain factor η measured in field trials (1.0 for blacktop or treadmill up to 2.1 for loose sand).
Watts are joules per second, so multiplying by the session length in seconds and dividing by 4,184 joules per kilocalorie gives calories. The "without the pack" figure reruns the equation with a zero load. The equation is gross energy expenditure (it includes resting metabolism) and is intended for level or uphill walking.
- M
- Metabolic rate in watts
- W
- Body mass in kg
- L
- Load (pack) mass in kg
- V
- Walking speed in m/s
- G
- Grade in percent
- η
- Terrain factor
Worked examples
80 kg, 15 kg pack, 5.5 km/h for an hour on pavement
Speed is 1.528 m/s. M = 1.5×80 + 2×95×(15/80)² + 1.0×95×(1.5×1.528²) = 120 + 6.7 + 332.6 = 459 W. Over 3,600 s that is 459 × 3600 ÷ 4184 ≈ 395 kcal.
180 lb with a 30 lb ruck at 3.5 mph, 5% grade, dirt trail, 90 min
180 lb = 81.6 kg, 30 lb = 13.6 kg, 3.5 mph = 1.565 m/s. The grade term adds a lot: 1.1 × 95.3 × (1.5×1.565² + 0.35×1.565×5) ≈ 672 W of the 799 W total, or about 1,032 kcal in 90 minutes.
Same 80 kg walker with no pack
With no load the load term vanishes: 1.5×80 + 80 × (1.5×1.528²) = 120 + 280.1 = 400.1 W, or about 344 kcal per hour. The 15 kg pack in the first example therefore adds roughly 51 kcal on flat pavement.
Frequently asked questions
How many calories does rucking burn?+
A typical 80 kg person carrying 15 kg at a brisk 5.5 km/h on flat pavement burns roughly 400 kcal per hour. Hills, soft terrain, heavier loads and faster pace can push it well above 600–800 kcal per hour.
Does rucking burn more calories than walking?+
Yes. The pack adds weight that must be supported and moved, and its effect grows with speed and grade. On the flat a moderate pack adds a modest amount, but uphill or on sand the extra burn becomes large.
What is the Pandolf equation?+
It is a formula published in 1977 by US Army Research Institute of Environmental Medicine scientists to predict the energy cost of walking with loads, based on body mass, load, speed, grade and terrain. It remains the standard military load-carriage model.
How heavy should my rucking pack be?+
Beginners often start with about 10% of body weight (8 kg / 18 lb for an 80 kg / 180 lb person) and add a little every week or two. Many experienced ruckers stay under about a third of body weight to protect the back, hips and feet.
Is the calculator accurate for downhill rucking?+
No. The original Pandolf equation does not handle negative grades well and overestimates the cost of descending. A later correction by Santee and colleagues addresses downhill walking; this calculator only accepts level or uphill grades.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.