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How to Calculate Mpg Calculator

What is Mpg Calculator?

Miles per gallon (MPG) is the standard measure of fuel economy in the UK and US — how many miles a vehicle travels on one gallon of fuel. The higher the MPG, the more fuel-efficient the car. Litres per 100km (L/100km) is used in continental Europe.

Step-by-Step Guide

  1. 1Fill the tank completely and note the odometer reading
  2. 2Drive normally until you need to refuel
  3. 3Fill the tank again and note: litres added and new odometer reading
  4. 4MPG = Miles driven / Gallons used (1 gallon = 4.546 litres in UK, 3.785 litres in US)

Worked Examples

Input
350 miles driven · 45 litres added (UK)
Result
35.3 MPG
45 L ÷ 4.546 = 9.9 gallons; 350 ÷ 9.9 = 35.3
Input
500 km · 40 litres
Result
8 L/100km
40÷500×100 = 8

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