Calculators for the road
Free, no-signup driving math — what gas will cost for a trip, how a new tire size compares (and what it does to your speedometer), and what it really costs to charge an EV. Each one shows its formula.
Gas Trip Cost Calculator
What fuel will cost for a drive — from the distance, your car's MPG, and the price per gallon.
Estimate gas costTire Size Calculator
Compare two tire sizes — diameter, width, and the speedometer error a size change causes.
Compare tiresEV Charging Cost Calculator
What a charge really costs — from your battery size or miles, efficiency, and electricity rate.
Estimate charging costMPG Calculator
Your real gas mileage — miles driven divided by the gallons it took to fill up.
Find your MPGCost Per Mile Calculator
What every mile costs in fuel, and the yearly total, from your gas price and MPG.
Cost per mileCar Depreciation Calculator
What your car will be worth in a few years, and how much value it loses annually.
Estimate valueGuides
Plain-English driving help — figuring gas for a road trip, what tire sizes mean, and what it costs to charge an EV.