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Fuel Cost Calculator Calculators

Work out what a journey costs in fuel, and split it between passengers.

Fuel Cost Calculator is a free online tool that work out what a journey costs in fuel, and split it between passengers. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.

Price
Free — no account, no quota, no watermark
Category
Calculators
Where it runs
In your browser, on your device
Files uploaded
None
Technology
plain JavaScript
Settings
8
Works offline
Yes, after the first visit

About Fuel Cost Calculator

The economy units are not interchangeable, and mixing them is the usual source of wrong answers: L/100km gets better as it falls, while MPG gets better as it rises. A US gallon is 3.785 liters and an imperial gallon is 4.546, which is why UK cars appear roughly 20% more efficient than identical US ones on paper.

How to use it

  1. Enter distance, distance unit and fuel economy.
  2. Adjust the remaining 5 settings if the defaults do not fit your case.

The 8 settings

SettingWhat it doesDefault
DistanceA numeric value.300
Distance unitChoose from 2: Kilometers, Miles.Kilometers
Fuel economyA numeric value.7.5
Economy unitChoose from 4: L / 100 km, MPG (US), MPG (imperial), km / L.L / 100 km
Fuel price per liter/gallonA numeric value.1.5
Split betweenRange 1–50.1
Return journeyOn or off. Off by default.Off
CurrencyChoose from 7: USD $, GBP £, EUR €, INR ₹, AUD A$, CAD C$….USD $

Under the hood

Runs onplain JavaScript — runs the whole thing
ControlsDistance, Distance unit, Fuel economy, Economy unit, Fuel price per liter/gallon, Split between, Return journey, Currency

Questions

Why is my real economy worse than the manufacturer figure?

Official figures come from standardized lab cycles. Real-world consumption is typically 10–25% higher, more in cold weather, city driving or with a roof box.

What does the economy unit option change?

It offers 4 choices — L / 100 km, MPG (US), MPG (imperial) and km / L. The default is L / 100 km, which suits most cases; change it when your input or your destination calls for something specific.

What are the limits on split between?

It accepts 1 to 50, starting at 1.

Is the arithmetic exact?

It uses double-precision floating point — about 15 significant figures, far more than the inputs justify. Displayed rounding is cosmetic; the underlying numbers are not rounded between steps, so chained results do not drift.