Free MPG Fuel Cost Calculator — Trip Gas Cost
Road trips feel cheap until the third fill-up. Enter your distance, your car’s real MPG, and the gas price along your route, and this calculator gives you the honest numbers: gallons burned, total fuel cost, cost per mile, and a per-person split for group trips — plus a comparison showing what the same trip costs at 25 and 40 MPG, which is eye-opening when you are car shopping.
MPG Fuel Cost Calculator
What will the drive actually cost? Gallons, total cost, cost per mile, and per-person splits in one click.
1 Your trip
2 Trip fuel cost
⛽ Your trip cost
How it works
Fuel cost is distance divided by MPG (gallons needed) multiplied by price per gallon. The round-trip toggle doubles distance before the math, and the comparison rows rerun the same formula at fixed 25 and 40 MPG so you can see the efficiency gap in dollars. All inputs are yours — no live gas prices are fetched, so use the price you actually see at your local stations.
Everyday uses
- Road trippers — budget the drive before booking the hotels.
- Commuters — turn a job offer’s longer drive into a real monthly number.
- Group trips — split fuel fairly with the per-person figure.
- Car shoppers — compare two cars’ MPG in dollars per trip, not just ratings.
Frequently asked questions
Why is my real cost higher than the estimate?
Roof boxes, heavy loads, winter gas, hills, and speeds above ~65 mph all cut real MPG. Bump the price or drop the MPG a little for a conservative budget.
Should I use city or highway MPG?
Use the combined figure your dashboard shows over the last tank or two — it reflects your actual driving mix.
Does premium fuel change the math?
Only through the price you enter. If your car requires premium, enter the premium price per gallon.