Gas mileage calculator

Frequently asked questions

What is a good MPG for a car?

Most modern passenger cars average somewhere between 25 and 40 MPG in combined driving, while trucks and SUVs typically fall in the 15–25 MPG range. The right benchmark depends on the vehicle class and whether the driving is mostly city or highway.

Why does the calculator show three different numbers?

MPG, km/L, and L/100 km all express the same underlying efficiency from different angles. MPG and km/L are distance-per-fuel ratios, while L/100 km is a fuel-consumption format common in European vehicle specs — a lower number means better efficiency.

Does the result change based on whether I enter miles or kilometers?

Yes. Select the unit system that matches your inputs — U.S. for miles and gallons, metric for kilometers and liters — and the calculator converts the primary result to all three formats automatically.

Why might my calculated MPG differ from the EPA window sticker?

Window-sticker figures are tested under controlled lab conditions. Real-world mileage varies with speed, traffic, temperature, cargo load, and driving style, so a single trip calculation rarely matches the official estimate exactly.