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How Many Calories Do You Burn in a Marathon?
A full marathon — 26.2 miles (42.2 km) — burns roughly 2,600–3,000+ calories for most runners, at around 100 calories per mile. Body weight is the main driver, so heavier runners burn well over 3,000.
Marathon calories by body weight
| Body weight | Calories (26.2 mi) |
|---|---|
| 55 kg (120 lb) | ~2,100 |
| 70 kg (155 lb) | ~2,650 |
| 85 kg (185 lb) | ~3,150 |
| 100 kg (220 lb) | ~3,700 |
Why fuelling matters
Your body only stores around 2,000 calories of glycogen — less than a marathon needs. That gap is the famous "wall." Taking in 30–60 g of carbs per hour (gels, drinks, chews) during the race keeps you from running empty in the final miles.
Plan your race
Estimate your own marathon burn with the calories calculator, set a realistic finish time with the race-time predictor, and lock in goal pace for the day.