Maintenance & Fuel · Free tool
Free Fuel Cost Calculator
Enter the distance, your fuel economy and the price at the pump to see how many gallons a trip needs and what it will cost.
- Free to use
- No signup
- Runs in your browser
What to cost
The car and the pump
Use highway MPG for a road trip.
Optional. Used to count fill-ups.
Fuel cost of the trip
$56.25
450 miles at 28 MPG.
- Fuel needed
- 16.1 gal
- Cost per mile
- $0.13
- Cost per person (1)
- $56.25
- Range on a full tank
- 392 miles
- Fill-ups needed
- 1.1
Speed, load, hills and weather all change fuel use. Leave a margin on a long trip.
An estimate from the figures you enter, not a quote. Read the disclaimer. Updated .
02Your result
What your fuel cost result means
Fuel is the running cost you can predict most exactly, because it depends on three numbers you already know.
- 01
Fuel cost
The gallons the journey needs multiplied by the price per gallon. It covers fuel only, not tolls, parking or wear.
- 02
Cost per mile
The figure to use when comparing two cars, or driving against flying or taking the train.
- 03
Fill-ups
How many tanks the distance needs, so you can plan stops on a long route.
What to do next
Measure your real MPG
A measured figure makes this estimate far more accurate than the brochure number.
MPG calculatorAdd every other cost
Fuel is one line. See depreciation, insurance and maintenance beside it.
Ownership cost calculatorUse less fuel
The habits and checks that cut fuel use, with the figures behind them.
Fuel economy guide
03How it works
The fuel cost formula
Work out the gallons first, then price them.
Fuel cost = (distance ÷ MPG) × price per gallon
Cost per mile = price per gallon ÷ MPG. Cost per person = fuel cost ÷ people sharing.
What each term means
- distance
- Miles to be driven. Double it for a round trip.
- MPG
- Your fuel economy in miles per US gallon. Use highway MPG for highway trips.
- price per gallon
- What you expect to pay at the pump.
- distance ÷ MPG
- The gallons of fuel the journey needs.
What the tool assumes
- Fuel economy stays constant over the whole distance.
- One fuel price for the whole journey.
- No allowance for idling, detours or traffic.
- Range is tank size multiplied by MPG, with no reserve kept back.
04Worked example
Fuel cost example: a 450-mile trip
A 450-mile drive in a car that averages 28 MPG, with gas at $3.50 a gallon and two people sharing the cost.
- 01
Work out the gallons
450 miles ÷ 28 MPG
16.1 gal
- 02
Price the fuel
16.1 gallons × $3.50
$56.25
- 03
Find the cost per mile
$3.50 ÷ 28 MPG
$0.13
- 04
Split it
$56.25 ÷ 2 people
$28.13
- 05
Double it for the return
$56.25 × 2
$112.50
Fuel cost, one way
$56.25
The round trip costs $112.50 in fuel, or $56.25 per person with two sharing.
Try your own numbers05Background
What decides the fuel cost of a trip
Three things set the bill: how far you go, how many miles the car covers per gallon and what a gallon costs. You control the second more than you might think, because the same car returns very different fuel economy on a steady highway and in stop-and-go traffic.
- AAA's average fuel cost per mile for a new vehicle, 2026
- 17.3¢
- a year at 15,000 miles, on that average
- $2,598
- a month, on the same figures
- $217
Use those averages as a yardstick, not a forecast. Your own cost per mile is the price of a gallon divided by your MPG, so a measured MPG figure gives a far better answer than a brochure one.
For ways to bring the number down, see the fuel economy section of the maintenance guide.
06When to use it
When to use a fuel cost calculator
Any time the question is what a journey, or a year of journeys, will cost in fuel.
Planning a road trip
Know the fuel bill and the number of fill-ups before you set off.
Splitting costs
Divide the fuel fairly between everyone in the car.
Budgeting a commute
Switch to yearly mode to see the monthly and weekly cost.
Comparing two cars
Run the same miles at each car’s MPG and compare the yearly totals.
Mistakes to avoid.
- Using city MPG for a highway trip, or the other way round.
- Forgetting the return leg.
- Using last month’s fuel price for a trip through a more expensive area.
- Treating fuel as the whole cost of driving. Tires, maintenance and depreciation add to every mile.
07Related guides and tools
Keep going from here.
Guides that go with this tool
Related tools
08Questions
Fuel Cost Calculator: your questions.
How do I calculate the fuel cost of a trip?
Divide the distance by your MPG to get the gallons needed, then multiply by the price per gallon. A 450-mile trip at 28 MPG needs about 16.1 gallons, which costs $56.25 at $3.50 a gallon.
How much gas will I use on a road trip?
Divide the miles by your car’s highway MPG. A 600-mile trip in a car that does 30 MPG on the highway uses 20 gallons.
What is the average fuel cost per mile?
AAA puts the average fuel cost for a new vehicle at 17.3 cents per mile in 2026. Your own figure is the price of a gallon divided by your MPG.
How do I split gas costs between passengers?
Work out the total fuel cost for the trip and divide it by the number of people sharing. The calculator does this when you enter the number of people.
Does speed change the fuel cost?
Yes. Fuel economy falls as speed rises above the car’s most efficient cruising speed, and hard acceleration and braking waste fuel as well.
09Estimates and sources
Read this before you rely on it.
Built and checked by CarTipsMentor Team. Last updated . How we check our work.
Sources
- [1]AAA, Your Driving Costs 2026 (brochure)
- [2]fueleconomy.gov (U.S. Department of Energy and EPA), Calculating Your MPG
- [3]fueleconomy.gov (U.S. Department of Energy and EPA), Driving More Efficiently