Smart Calculator Pro

Smart Calculator Pro

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Fuel Cost Calculator

Estimate how much gas you will need and what it will cost for any trip. Enter the distance, your vehicle's fuel efficiency, and the current gas price to see the total fuel required, total cost, and cost per mile.

The total distance of your trip in miles.

Your vehicle's fuel efficiency in miles per gallon. Check your owner's manual or fueleconomy.gov.

The current price of gas per gallon in dollars.

This calculator divides your trip distance by your vehicle's fuel efficiency to determine how many gallons of fuel you need, then multiplies by the gas price to give you the total trip cost. It also calculates the cost per mile so you can compare driving costs across different vehicles or routes.

How It Works

Fuel Cost Formula

Total Cost = (Distance / MPG) x Price Per Gallon

The total fuel cost equals the trip distance divided by fuel efficiency (miles per gallon), then multiplied by the gas price per gallon.

Total fuel needed = distance / fuel efficiency (MPG)

Total cost = fuel needed x price per gallon

Cost per mile = price per gallon / fuel efficiency (MPG)

Important Notes:

  • •Actual fuel consumption varies with driving conditions, speed, terrain, weather, and vehicle load
  • •Highway driving typically yields better MPG than city driving
  • •The EPA fuel economy rating is an estimate; real-world MPG often differs by 10-20%
  • •Gas prices vary by region and change frequently

Worked Example

A 300-mile road trip in a car that gets 25 MPG, with gas at $3.50 per gallon.

Inputs:

  • distance:300
  • fuel Efficiency:25
  • fuel Price:3.5

Result:

The trip requires 12.0 gallons of gas, costing $42.00 total. The cost per mile is $0.140.

Who Is This Calculator For?

  • road trip planners
  • commuters budgeting fuel costs
  • anyone comparing vehicle fuel expenses

Frequently Asked Questions

Check your vehicle's window sticker (for new cars), owner's manual, or look it up on fueleconomy.gov by entering the make, model, and year. You can also calculate it yourself by filling your tank, driving until you need to refuel, noting the miles driven and gallons used, and dividing miles by gallons.
Use highway MPG if most of your trip is on highways and interstates. Use city MPG for urban or stop-and-go driving. For mixed trips, use the combined MPG rating, or calculate a weighted average based on the proportion of highway versus city driving.
At the U.S. average of about 25 MPG and $3.50 per gallon, driving 1,000 miles costs approximately $140. A more fuel-efficient car at 35 MPG would cost about $100 for the same distance, while a truck at 18 MPG would cost about $194.
Keep your tires properly inflated, drive at moderate speeds (fuel efficiency drops significantly above 50 mph), avoid aggressive acceleration and braking, remove unnecessary weight from your vehicle, use cruise control on highways, and keep up with regular maintenance like oil changes and air filter replacements.
Yes. If you are planning a round trip, enter the total distance for both legs combined. For example, if your destination is 150 miles away, enter 300 miles to account for the return trip. This gives you the total fuel cost for the entire journey.
Driving is often cheaper than flying for trips under 300-400 miles, especially with multiple passengers splitting fuel costs. For solo travelers on longer trips, flying may be more cost-effective when you factor in time and wear on your vehicle. Train costs vary widely by route and how far in advance you book.

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Last updated: April 20, 2026