Fuel & units

km/L to MPG: Japan, India and Korea

By RoadCost Editorial4 min readUpdated 27 October 2026

Japan, India and South Korea often quote fuel economy in kilometres per litre. It is a distance-per-fuel unit, like MPG, so higher is better. The difference is the fuel volume and the distance unit, not the underlying idea.

Quick answer

1 km/L equals about 2.352 MPG US or 2.825 MPG UK. To convert km/L to L/100 km, divide 100 by the km/L figure.

In this guide

1. The conversion formulas
2. Worked examples
3. Using km/L in a fuel-cost estimate
Questions

Key takeaways

Higher km/L is better.
1 km/L is about 2.35 MPG US.
L/100 km = 100 ÷ km/L.

The conversion formulas

A kilometre is shorter than a mile, and a litre is smaller than a US gallon. The conversion factor therefore combines both differences. The result is a simple multiplier.

MPG (US) = km/L × 2.352145
MPG (UK) = km/L × 2.824809
L/100 km = 100 ÷ km/L

Worked examples

A car using 15 km/L is using about 6.67 L/100 km. That is roughly 35.3 MPG US or 42.4 MPG UK. A car using 20 km/L is using 5 L/100 km, which is more efficient.

km/L converted to common fuel-economy units
km/L	L/100 km	MPG US	MPG UK
10	10.0	23.5	28.2
15	6.67	35.3	42.4
20	5.0	47.0	56.5
25	4.0	58.8	70.6

Using km/L in a fuel-cost estimate

The fuel-cost formula is straightforward: litres used = kilometres ÷ km/L. Multiply by the price per litre to get the cost. If you are comparing with a UK or US figure, convert everything to L/100 km first so the direction of improvement is obvious.

Our fuel-cost calculator includes Japan, India and South Korea presets that accept km/L directly.

Questions

How many km/L is 40 MPG?

40 MPG US is about 17.0 km/L. 40 MPG UK is about 14.2 km/L, because the imperial gallon is larger.

Why do some countries use km/L?

It is a familiar distance-per-fuel measure. Like MPG, it is easy to understand when fuel is sold by the litre and distances are in kilometres.

Is 20 km/L good?

It is about 5 L/100 km, which is efficient for many petrol cars, but the right comparison depends on vehicle size and driving conditions.

Sources

NIST — unit conversion — US customary and metric relationships used by the converters.
UK Weights and Measures Act 1985 — Statutory context for UK units, including the imperial gallon.
fueleconomy.gov — US fuel-economy ratings — EPA label values, test-cycle context and consumer guidance.
GOV.UK — weekly road fuel prices — UK price statistics for context, not a live station price.
US EIA — gasoline and diesel prices — US regional and national averages.

Try the calculator

Fuel cost calculator

Includes Japan, India and South Korea km/L presets.

Related guides

L/100 km to MPG: exact conversion

Turn litres per 100 kilometres into UK or US MPG with the exact formulas, examples and a simple way to remember the ratio.

MPG to L/100 km: exact conversion

Convert MPG to L/100 km with the right constant for UK and US gallons, including worked examples and common mistakes.

Fuel economy vs consumption

MPG and km/L measure distance per fuel. L/100 km measures fuel per distance. Here is why the distinction matters for comparisons and costs.

A note on prices and rules

This guide explains arithmetic and units. It does not publish live fuel prices, electricity tariffs or changing tax rules. Use your own price and check official sources for anything that changes.

Page last reviewed: 27 October 2026. Formulas are covered by automated tests. Prices are inputs, not live data.