Gas Mileage Calculator (MPG)
Calculate your real-world fuel economy from distance driven and fuel used, in MPG and L/100km, with cost per mile.
Fuel economy
26.20
Breakdown
- Unit
- MPG (US)
- L/100km equivalent
- 9
- Cost per mi/km
- $0.13
- Total fuel cost
- $50.75
Last updated:
FAQ
How do I measure my real MPG?
Fill the tank, reset the trip meter, drive normally, refill, then divide miles driven by gallons on the second fill. One tank is enough; average 3 tanks for accuracy.
Why does my dashboard MPG disagree with my math?
Trip computers estimate from fuel-injector flow and often read 2–5% optimistic. The fill-up method — miles driven ÷ gallons added — is the ground truth.
Is highway or city driving more efficient?
Highway by 20–40% for most cars: steady speed avoids acceleration losses. Hybrids flip this in stop-and-go traffic.
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