What is the formula to convert L/100km to MPG (UK)?

MPG (UK) = 282.481 ÷ L/100km. The constant 282.481 comes from the number of liters in a UK imperial gallon (4.54609) multiplied by meters per mile (1609.344), divided by 1000. For example, 8 L/100km converts to 282.481 ÷ 8 = 35.31 MPG (UK).

Why is the relationship between L/100km and MPG inverse?

L/100km measures fuel consumed per unit of distance, while MPG measures distance traveled per unit of fuel. A lower L/100km means better efficiency, but a higher MPG also means better efficiency — they move in opposite directions.

How do I convert UK MPG back to L/100km?

L/100km = 282.481 ÷ MPG (UK). For example, 40 MPG (UK) converts to 282.481 ÷ 40 = 7.06 L/100km.

What is 6 L/100km in UK MPG?

6 L/100km = 282.481 ÷ 6 = 47.08 MPG (UK).

What is the difference between UK MPG and US MPG?

The UK imperial gallon is larger (4.54609 L) than the US gallon (3.785411784 L), so UK MPG figures are always about 20% higher than US MPG for the same vehicle. The conversion constant for UK MPG is 282.481; for US MPG it is 235.215.

L/100km to MPG (UK) Converter

Name: L/100km to MPG (UK) Converter
Availability: InStock
Author: Nham Vu

Enter L/100km to get UK MPG instantly — or enter UK MPG to get L/100km. Includes a reference table for common values.

Fuel Economy Converter

L/100km (liters per 100 km)

= UK MPG —

UK MPG (imperial miles per gallon)

= L/100km —

Formula: MPG (UK) = 282.481 ÷ L/100km Imperial gallon = 4.54609 L

Reference Table

Click a row to load it into the converter.

L/100km	MPG (UK)	Label

Summary

Enter L/100km to get UK MPG instantly — or enter UK MPG to get L/100km. Includes a reference table for common values.

How it works

Enter a fuel consumption value in L/100km in the top field.
The UK MPG result appears instantly using the formula: MPG (UK) = 282.481 ÷ L/100km.
Use the reverse field to convert UK MPG back to L/100km.
Click "Copy" next to any result to copy it to your clipboard.
Click any row in the reference table to load that value into the converter.

Use cases

Compare European car specs (L/100km) to the UK WLTP MPG standard.
Convert a foreign car listing fuel figure before buying or importing to the UK.
Understand fuel costs when driving in the UK after reading European specs.
Verify manufacturer efficiency claims published in different markets.
Calculate fuel budget for a UK road trip from a metric fuel consumption figure.
Convert modern L/100km ratings for classic cars bought overseas.

Frequently Asked Questions

Last updated: 2026-07-23 · Reviewed by Nham Vu