Gas Calculator

Divide the miles you will drive by your car's miles per gallon to get the gallons, then multiply the gallons by the price of a gallon. For 250 miles at 25 mpg and $3.50 a gallon, that is 250 ÷ 25 = 10 gallons and 10 × $3.50 = $35.00. Another way to see it: the cost per mile is the price divided by the mpg, here $0.14, so any distance costs that rate times the miles.

Divide the total miles by your mpg. A 500-mile drive needs 20 gallons at 25 mpg, 16.7 gallons at 30 mpg and 25 gallons at 20 mpg. Count the drive back if you are returning, and leave some margin if you expect hills, heavy traffic or a full load.

This calculator does not load prices, so it uses exactly the price per gallon you type. The result is only as accurate as that price and your mpg. Prices differ between stations and move over time, so use the price on the sign where you plan to buy, and look at the price chart under the calculator to see what the same gallons cost at higher prices.

Never, because the page keeps no price list. You enter the price yourself, so the result is as current as the number you type. Check the pump sign or a price comparison app before you leave, and change the price field if it moves. The price chart shows the cost of the same gallons at prices from $2.50 to $7.00.

Yes, once you convert to miles, mpg and a price per US gallon. Divide kilometers by 1.609 to get miles, divide 235.215 by a L/100 km figure to get mpg (7.84 L/100 km is 30 mpg) and multiply a price per liter by 3.785 (1.50 per liter is 5.68 per gallon). UK mpg figures count imperial gallons of 4.546 liters, so the same car shows a number about 20% higher in UK mpg than in US mpg.

Any fuel you buy by the gallon: regular, midgrade or premium gasoline, or diesel. Enter the price per gallon of the fuel you use and the mpg you get on it. Electric cars use kilowatt-hours instead of gallons, so they need the calculation in the electric vehicle answer below.

The highest mpg your car actually gets at steady highway speeds, since a higher mpg means fewer gallons for the same miles: 500 miles take 25 gallons at 20 mpg but only 16.7 gallons at 30 mpg. For the estimate, use the highway estimate on the EPA label of a new car, or your own mpg from a fill-up on a similar drive, rather than the city figure.

This calculator cannot look up local prices because it has no location data. Read the price signs along your route or use a price comparison app, then type the prices into the calculator. To see what a cheaper station saves, run both prices: on a 12-gallon fill-up, a price that is 20 cents lower saves $2.40.

Yes. Gas depends only on the total miles, not on the stops, so add up every leg, including the drive home, and enter the sum as the distance. If the legs have very different mpg, such as city streets and highway, run each leg on its own and add the costs. If gas prices differ along the route, enter an average price.

The arithmetic is exact, so the estimate is as good as the mpg you enter. Real-world mpg changes with speed, hills, traffic, weather, load and how you drive, so a label figure can be off. For a better number, use the fill-up option to measure your own mpg over a few tanks and enter that figure. Tolls and parking are not included.

Petrol is the British word for gasoline. The two fuels have their own price per gallon, and a car has its own mpg on each, so the fair comparison is the cost per mile, which is the price per gallon divided by the mpg. Run the calculator once with the gasoline price and mpg and once with the diesel price and mpg, then compare the cost per mile.

An electric car uses kilowatt-hours instead of gallons. Multiply the kWh the car uses per mile by the price of a kWh. For example, a car that uses 0.3 kWh per mile on electricity at $0.17 per kWh costs about $0.05 a mile, so 250 miles cost about $12.75. This calculator is built for gallons, so it does not do that math for you.

The main ones are how fast and how smoothly you drive, hills and traffic, the weight you carry, tire pressure, the weather and the fuel itself. The EPA notes that gasoline with up to 10% ethanol (E10) gives slightly lower fuel economy than gasoline without ethanol. Because these change from trip to trip, treat the result as an estimate and measure your own mpg over several tanks.

The easiest way is the fill-up option in this calculator. Fill the tank, reset the trip meter, drive as you normally do, then fill the tank to the same level and note the gallons. Miles divided by gallons is your gas mileage in miles per gallon (mpg). For a new car, the fuel economy label lists EPA city and highway estimates, which you can use until you have a figure of your own.

The gas part of the cost per mile is the price per gallon divided by the mpg: $3.50 at 25 mpg is $0.14 a mile, $3.50 at 35 mpg is $0.10 and $4.50 at 18 mpg is $0.25. The chart of mpg values shows the cost per mile at your gas price. Gas is only part of the cost of driving, which also includes insurance, maintenance, tires and depreciation.

Enter the number of people sharing the cost, including the driver, and the calculator divides the total by that number. Two people sharing a $35.00 trip pay $17.50 each, and four people pay $8.75 each. The cost per mile in the results helps if a rider joins for only part of the route.

Choose the monthly option. Enter the miles you drive on a driving day, the driving days per week, your mpg and the gas price. The calculator multiplies the miles by the days and by 52 weeks, divides by 12 months, divides by the mpg to get gallons and multiplies by the price. Driving 30 miles a day, five days a week, at 25 mpg and $3.50 a gallon comes to 26 gallons and $91.00 a month.