GasCalculator.org is a free online toolkit for drivers, built around one simple question: how much will this trip cost in gas? Our flagship gas calculator answers it in seconds — and shows its math openly, so you never have to trust a black box.
What We Offer
Seven free calculators, each with its formula published on the page: a Gas Calculator, MPG Calculator, Fuel Cost Calculator, Trip Cost Calculator, Cost Per Mile Calculator, Gas Mileage Calculator and an EV vs Gas Cost Calculator. Every tool runs entirely in your browser — no downloads, no sign-up, and nothing you enter is sent to or stored on our servers.
How We Work
We use the same standard formulas used across the industry — for fuel cost, (Distance ÷ MPG) × Price — and we document our data sources and review process on our Methodology & Sources page. Reference figures such as fuel-economy ratings and mileage rates are drawn from public sources including the U.S. Energy Information Administration (EIA), the U.S. EPA’s FuelEconomy.gov and the IRS.
Our Mission
Driving is one of the biggest everyday expenses, yet most people only learn what a trip costs after they have paid for it. Our mission is to make driving costs clear before you turn the key — for road trips, commutes, shared rides and business miles alike.
Why Free?
These are simple, honest calculations that should be free for everyone. The site is maintained as a public resource; we may show advertising in the future to cover hosting costs, but the calculators will always be free to use.
Get in Touch
Corrections, suggestions and questions are welcome via our Contact Us page or by email at admin@gascalculator.org. Accuracy matters to us — if you spot an error, tell us and we will fix it.
Last updated: October 23, 2026.