How to Calculate Gas Mileage
What is Gas Mileage?
Gas mileage (or fuel economy) measures how efficiently a vehicle uses fuel. In the US, this is miles per gallon (MPG); in the UK, also MPG but using the larger imperial gallon; in most other countries, litres per 100km (L/100km).
Formula
- MPG
- Miles driven / Gallons used — Miles driven / Gallons used
Step-by-Step Guide
- 1MPG = Miles driven / Gallons used
- 2L/100km = Litres used / (Distance in km / 100)
- 3Cost per mile = Fuel price per gallon / MPG
Worked Examples
Frequently Asked Questions
What is Gas Mileage?
Gas mileage (or fuel economy) measures how efficiently a vehicle uses fuel. In the US, this is miles per gallon (MPG); in the UK, also MPG but using the larger imperial gallon; in most other countries, litres per 100km (L/100km)
How accurate is the Gas Mileage calculator?
The calculator uses the standard published formula for gas mileage. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Gas Mileage calculator use?
This calculator works with inches, kilometres, miles, litres. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Gas Mileage calculator use?
The core formula is: MPG = Miles driven / Gallons used. Each step in the calculation is shown so you can verify the result manually.
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