About MPG Calc

Last updated: April 2026

What is MPG Calc?

MPG Calc is a free UK website for tracking fuel economy and finding the cheapest fuel near you. It brings together live fuel prices from over 6,500 UK stations with a suite of calculators to help you understand and reduce your motoring costs.

What can you do here?

  • Find cheap fuel — search by town, postcode area, or brand to compare live prices at nearby stations
  • Calculate your MPG — work out your real-world fuel economy from fill-up data
  • Compare running costs — side-by-side comparisons of two cars, including fuel, insurance, tax, and depreciation
  • Plan journeys — estimate fuel cost for a trip based on distance, MPG, and current fuel prices
  • Track your spending — create a free account to log fuel purchases and monitor your costs over time

Where does the data come from?

Fuel prices are sourced from the UK Government Fuel Finder scheme, which requires retailers to report their pump prices. Prices are refreshed every 30 minutes. Crude oil market data is sourced from Yahoo Finance (Brent crude futures, BZ=F).

The raw data isn't always clean — retailers occasionally file prices in the wrong field, or report obvious test/placeholder values. Every refresh is run through a statistical validation pipeline that either corrects or flags implausible prices before they reach the site. A non-technical overview is on the data quality page.

How we make money

MPG Calc is free to use and the calculators do not require an account. Optional features (logging fuel records against your own vehicles) require a free account which stores no personal information beyond an email address. We don't sell or share data. The site is designed to be funded by unobtrusive contextual advertising — no personalised tracking, no consent banner.

Editorial independence

Brand league tables, cheapest/most expensive listings and price signals are computed mechanically from the underlying data. No retailer pays for placement, and no retailer is excluded from the rankings except where their reported prices fail our statistical sanity checks (in which case the exclusion and the reason are visible on their station page).

About the author

I'm Charlie Trevor, a DevOps engineer based in the UK. I have been calculating the MPG of my own cars for around 16 years — initially on paper in a filofax, then via a Perl script around 14 years ago, then a Go CLI in 2023, and finally this website when I realised the calculators might be useful to other people too. The motivation is part stinginess, part curiosity about where the money actually goes when you fill the tank.

I have ~25 years of professional experience building and operating production systems on Linux, with a long background in Perl and more recent work in Go, Kubernetes, Terraform and the major cloud platforms. The site is built and maintained by me alone in my spare time.

Contact

If you spot a bug, have a feature request, or want to flag a station with persistently wrong prices, please email charlie@equusit.co.uk. I read everything; I usually reply within a day or two.