About DriveCostGuru

DriveCostGuru is a free set of calculators for drivers. We answer practical questions — what a road trip will cost in gas, whether an electric car saves money, and how a new tire size changes your speedometer — using clear formulas and official price data.

How we build our calculators

Every calculator uses a published formula that we show on the page, so you can check the math yourself. Where a tool uses prices or rates, we name the source (for example the U.S. Energy Information Administration) and the date of the data. When the source publishes new numbers, the site is updated.

Our promise

• Free to use, no sign-up.
• Formulas shown on every page.
• Sources and dates listed for all data.
• Corrections welcome — tell us if something looks wrong.