Round trip fuel calculator

FREE · NO ACCOUNT

Default gas price $3.995/gal (EIA Gasoline and Diesel Fuel Update, U.S. regular, week of Nov 9, 2026); other defaults are illustrative. Confirm local fuel and electricity rates before planning.

Round trip math

With symmetrical outbound and return mileage, total distance is twice the one-way distance. Fuel gallons = total miles ÷ MPG. This tool also assumes the same toll charge each way; adjust manually if your route differs.

When the two directions differ

Traffic, detours, one-way streets and toll rules can make the return route different. If that matters, calculate the legs separately rather than relying on a mirrored estimate.

Frequently asked questions

Does round trip always mean double the price?

Only when the route, efficiency and toll assumptions are the same both ways.

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