Map directions usually show one-way distance by default — plug that straight into a fuel cost calculator for a round trip and the real cost comes out double what you budgeted for. It's an easy mistake, and an easy one to build a fix for.
Trip gas cost calculator, distance × MPG × price
Enter the trip distance, your vehicle's MPG, and the price per gallon to get the total fuel cost and gallons needed — the straightforward version of the calculation.
How much will gas cost, round trip included
Toggle "Round trip" to automatically double the distance rather than doing the math yourself (and rather than forgetting to) — the gallons and cost update immediately.
Road trip fuel calculator, find your real MPG first
If you're not sure of your actual MPG, the Gas Mileage Calculator computes it from your real fill-up data rather than relying on the window-sticker EPA estimate.
