How running calories are calculated
This calculator uses the ACSM running equation from the American College of Sports Medicine’s Guidelines for Exercise Testing and Prescription, the standard reference used in exercise science. It estimates oxygen consumption from speed and gradient, then converts oxygen to energy at about 5 kcal per litre:
kcal/min = VO₂ × body weight (kg) ÷ 1000 × 5
speed in metres per minute, grade as a fraction
The final “+ 3.5” is your resting metabolism (one MET). Including it gives gross calories; leaving it out gives net calories — the energy the run itself added on top of what you would have burned sitting still.
The 1 kcal per kg per km rule
Something neat falls out of the ACSM equation. On flat ground, the net energy cost of running works out to almost exactly 1 kcal per kilogram of body weight per kilometre, whatever your speed. A 60 kg runner burns about 600 kcal of net energy over 10 km, whether they run it in 45 minutes or 75.
Distance matters more than speed. Running faster burns more calories per minute but finishes the distance sooner, so the total for a given distance barely changes. If you want to burn more energy, run further or add hills.
Calories burned running: chart by weight and distance
Net calories for flat running at a typical pace. Gross calories are roughly 10–20 % higher depending on how long the run takes.
| Weight | Per km | Per mile | 5K | 10K | Half | Marathon |
|---|---|---|---|---|---|---|
| 50 kg (110 lb) | 50 | 80 | 250 | 500 | 1055 | 2110 |
| 55 kg (121 lb) | 55 | 88 | 275 | 550 | 1160 | 2321 |
| 60 kg (132 lb) | 60 | 97 | 300 | 600 | 1266 | 2532 |
| 65 kg (143 lb) | 65 | 105 | 325 | 650 | 1372 | 2743 |
| 70 kg (154 lb) | 70 | 113 | 350 | 700 | 1477 | 2954 |
| 75 kg (165 lb) | 75 | 121 | 375 | 750 | 1582 | 3165 |
| 80 kg (176 lb) | 80 | 129 | 400 | 800 | 1688 | 3376 |
| 85 kg (187 lb) | 85 | 137 | 425 | 850 | 1794 | 3587 |
| 90 kg (198 lb) | 90 | 145 | 450 | 900 | 1899 | 3798 |
| 100 kg (220 lb) | 100 | 161 | 500 | 1000 | 2110 | 4220 |
| 110 kg (243 lb) | 110 | 177 | 550 | 1100 | 2321 | 4642 |
How hills change the numbers
Gradient is the biggest single multiplier. The ACSM equation adds 0.9 ml/kg/min of oxygen for every metre per minute of speed multiplied by the grade. At 10 km/h, a 5 % climb increases the net energy cost by about 22 %; a 10 % climb by about 45 %. On the flip side, downhill running costs less energy — but the equation is designed for level and uphill running, so use a grade of 0 for rolling courses.
| Grade | Net kcal/km (70 kg, 10 km/h) | vs flat |
|---|---|---|
| 0 % | 70 | — |
| 2 % | 76 | +9 % |
| 4 % | 83 | +18 % |
| 6 % | 89 | +27 % |
| 8 % | 95 | +36 % |
| 10 % | 102 | +45 % |
Running vs walking
Per kilometre, running costs roughly twice the net energy of walking at normal speeds, because you lift your body off the ground with every stride. Per minute, the difference is even bigger. But walking is lower impact and easier to sustain, so for many people the best activity is the one they will actually do consistently.
How accurate are calorie estimates?
- Equations like this one describe an average person. Your real energy cost depends on running economy, which varies by around 10–20 % between individuals of the same weight.
- Fitness trackers add heart-rate data but studies of wrist-worn devices frequently find energy-expenditure errors of 20–40 % or more.
- Afterburn (EPOC) — the extra energy used after exercise — is real but modest for steady runs, usually a small fraction of the run’s total.
Fuel your running. Calorie numbers are estimates, and running performance and health depend on eating enough to support your training. If you are using running to manage your weight, a registered dietitian can help you do it in a sustainable way.
Want a more precise picture of how hard a run was? Pair this with the heart rate zone calculator, or use the treadmill calculator to see how incline changes your effort.
- American College of Sports Medicine (2021). ACSM’s Guidelines for Exercise Testing and Prescription, 11th ed. Metabolic calculations appendix.
- Shcherbina A et al. (2017). Accuracy in wrist-worn, sensor-based measurements of heart rate and energy expenditure in a diverse cohort. J Pers Med 7(2):3.
Last reviewed: September 2026 · Health disclaimer