About this site
Kilometer-Mileage.com is a small set of calculators for distance, vehicle mileage and fuel costs. It exists because the same handful of questions come up constantly and most answers online are buried under adverts, sign-up walls or a page of preamble.
What you can do here
- Convert kilometers to miles and back.
- Work out your car's real fuel economy from a tank of fuel.
- Translate a fuel economy figure between US MPG, imperial MPG, km/L and L/100km.
- Estimate the fuel and cost of a planned journey.
Where the numbers come from
Distance conversions use the international mile, defined as exactly 1,609.344 metres by the 1959 international yard and pound agreement. Fuel volumes use the US liquid gallon at 3.785411784 litres and the imperial gallon at 4.54609 litres. These are exact definitions, not approximations, so the only rounding on this site happens when a result is displayed.
How it is built
Every calculator runs in your browser. Nothing you type is sent anywhere, stored, or used to build a profile of you. The pages are plain HTML and a single small script, which is why they load quickly on a phone with one bar of signal at a petrol station.
How the numbers are chosen
Two rules govern every figure here. First, where an exact definition exists, we use it and round only the display, never the calculation. Second, where more than one convention exists, we show both rather than picking the one that flatters. That is why fuel economy results appear in US MPG, imperial MPG, km/L and L/100km at the same time instead of assuming which country you are in.
Worked examples in the explanatory text are computed from the same constants the calculators use, so an example and a calculator can never disagree with each other.
What this site deliberately does not do
- No account, because a distance conversion does not need to know who you are.
- No newsletter, no pop-up asking for your email, no notification prompt.
- No analytics, so there is no record of what you converted.
- No auto-playing anything, and no layout that shifts under your thumb as the page finishes loading.
Who it is for
Three groups, roughly. Drivers checking what their car is actually doing or budgeting a journey. Travellers reading road signs, rental agreements and vehicle specifications in units they do not normally use. And students checking unit-conversion homework, which is why every calculator page shows the formula alongside the answer rather than just the answer.
Corrections
If you find a wrong figure, a broken calculator or an explanation that could be clearer, send it to contact@kilometer-mileage.com. Corrections get priority over everything else, and there is no ego attached to being told a number is wrong.