A Boeing 737 burns roughly 2,200–2,600 kg of fuel per cruise hour. Compare 737 variants and see why real-world and simulator figures vary.
A Boeing 737 typically burns 2,200–2,600 kg (4,850–5,730 lb), about 725–855 US gallons, of fuel per cruise hour. A 737-800 usually sits near the upper half of that range, while a 737 MAX 8 is generally lower. Flight phase, weight, altitude, weather and engine fit can shift the figure substantially.
In aviation and real-world flying, there is no single certified “737 per hour” figure. Airlines calculate fuel for the exact aircraft, payload, route, forecast winds and operating conditions rather than using a family-wide average.
How much fuel does each Boeing 737 variant burn?
Representative two-engine cruise fuel flow ranges from about 2,000 kg/h in an efficient, lightly loaded MAX to around 3,000 kg/h in an early 737.
| 737 generation or variant | Typical cruise burn | Approximate US gallons per hour |
|---|---|---|
| 737-100/-200 | 2,500–3,000 kg/h (5,500–6,600 lb/h) | 820–990 |
| 737 Classic (-300/-400/-500) | 2,300–2,700 kg/h (5,100–6,000 lb/h) | 760–890 |
| 737 NG (-600/-700) | 2,100–2,400 kg/h (4,600–5,300 lb/h) | 690–790 |
| 737 NG (-800/-900ER) | 2,400–2,700 kg/h (5,300–6,000 lb/h) | 790–890 |
| 737 MAX 8/9 | 2,000–2,400 kg/h (4,400–5,300 lb/h) | 660–790 |
These are broad cruise estimates, not aircraft flight manual or dispatch figures. The gallon conversions assume Jet A at roughly 6.7 lb per US gallon; density changes with temperature and fuel grade. Imperial gallons are larger and must not be confused with US gallons.
Is 850 gallons per hour accurate for a 737-800?
About 850 US gallons per hour is a reasonable shorthand for a 737-800 in steady cruise, corresponding to roughly 2,580 kg or 5,700 lb per hour. It should not be treated as the aircraft’s consumption during every hour of a flight.
Take-off and climb produce much higher instantaneous fuel flow, while descent requires far less. Taxi and APU operation also consume fuel without contributing cruise distance, so block fuel divided by block time will not necessarily equal the cruise figure.
Why does Boeing 737 fuel consumption vary?
Weight, flight level, speed and configuration can move the hourly figure by hundreds of kilograms.
- Aircraft weight: A heavily loaded aircraft early in the flight needs more thrust. Cruise burn normally falls as fuel is consumed.
- Altitude and speed: Flying below the optimum level or faster than the planned cost index increases consumption. Step climbs can improve efficiency on longer sectors.
- Weather: Temperature and turbulence affect performance. A headwind mainly raises total trip fuel by extending flight time rather than automatically changing the engine’s hourly fuel flow.
- Aircraft configuration: Anti-ice, bleed-air demand, drag from an abnormal configuration and a dirty airframe all carry a fuel penalty.
- Generation and engines: Early JT8D-powered aircraft, CFM56-powered Classics and NGs, and LEAP-1B-powered MAX aircraft do not burn fuel at the same rate. Our explanation of the MAX’s engine and aerodynamic changes covers the main efficiency differences.
How do I estimate 737 fuel for a flight?
For a rough cruise estimate, multiply expected cruise time by the combined hourly fuel flow of both engines.
For example, a 737-800 cruising for two hours at 2,500 kg/h uses approximately 2.0 h × 2,500 kg/h = 5,000 kg during that cruise period. That is not the amount that should be loaded.
Real block fuel must also account for taxi, take-off, climb, descent, approach, contingency, an alternate where required, final reserve and any additional operational fuel. Real-world crews and dispatchers use approved performance and flight-planning data; a generic hourly estimate is not suitable for operational planning.
Why does my flight simulator show a different fuel burn?
Simulator readings often differ because users compare different units, flight phases or engine totals rather than because the aircraft is necessarily modelled incorrectly.
- Add both engines: Many 737 engine displays show separate left and right fuel-flow values. A reading of 1,250 kg/h per engine means 2,500 kg/h total.
- Check the units: Confusing pounds with kilograms creates a 2.205-to-one error. Gallons introduce another variable because fuel quantity by volume depends on density.
- Use a stable cruise condition: Compare figures with the aircraft clean, level and settled at cruise thrust. Take-off fuel flow is not representative.
- Measure simulated time: Time acceleration changes fuel used per real-world clock hour. Base the calculation on elapsed simulator time.
- Account for the APU: Fuel lost from the tanks can include APU consumption even though the engine display reports only engine fuel flow.
- Check aircraft setup: Incorrect payload, cruise altitude, cost index or route data can spoil predicted fuel. Correctly entering route, payload and fuel data in the 737 FMC produces a more meaningful destination estimate.
For quick simulator planning, we use about 2,500 kg/h for a 737-800 and 2,200 kg/h for a MAX 8, then replace that estimate with the aircraft’s own performance calculation once the route, weather and payload are known.