Mileage Calculator
Calculate real-world fuel economy in MPG and L per 100km plus trip fuel cost from distance and fuel used using this free mileage calculator. Enter miles or kilometers, gallons or liters, and optional fuel price to instantly see your vehicle efficiency and driving cost. Works offline with no signup required ever in Austin, Chicago, Miami, Denver, Seattle, and New York.
Calculate fuel mileage, efficiency and trip cost instantly. Free online mileage calculator with MPG, L/100km and fuel-cost estimates.
Calculator Inputs
About Mileage
Calculate real-world fuel economy in MPG and L per 100km plus trip fuel cost from distance and fuel used using this free mileage calculator. Enter miles or kilometers, gallons or liters, and optional fuel price to instantly see your vehicle efficiency and driving cost. Works offline with no signup required ever in Austin, Chicago, Miami, Denver, Seattle, and New York.
How MPG and fuel-cost math works: Divide distance by fuel used to get MPG. Divide 235.214 by MPG to convert to L per 100km, the metric standard. Multiply fuel used by price per gallon for trip cost. The calculator accepts miles or kilometers and gallons or liters, converting automatically. A 300-mile trip using 12 gallons at $3.50 per gallon gives 25 MPG, 9.41 L per 100km, and $42.00 total cost.
MPG versus L per 100km explained: MPG measures distance per unit of fuel where higher is better. L per 100km measures fuel per unit of distance where lower is better. They are inverses: 25 MPG equals 9.41 L per 100km. US consumers use MPG. European and Asian markets use L per 100km. The calculator shows both for cross-market comparisons. Austin buyers compare 28 MPG sedans. Miami fleets compare 18 MPG vans. Denver truckers compare 12 MPG rigs.
Trip cost and budgeting scenarios: Austin commuters compute 300-mile $42 daily drives from Round Rock. Chicago rideshare drivers track 150-mile $24 airport runs. Miami delivery fleets measure 200-mile $40 routes. Denver truckers calculate 500-mile $150 hauls. Seattle delivery vans compute 100-mile $14 routes. New York taxi fleets track 80-mile $16 daily circuits. Enter the pump price to cost every trip. Fuel cost is the second-largest ownership expense after depreciation for most US vehicles.
The tank-fill method for accuracy: Fill the tank completely, reset the trip meter, drive normally, then refill and note gallons pumped. Divide trip miles by gallons for accurate real-world MPG. Average three or more tanks for a stable figure because single fills vary with traffic, weather, and driving style. A 25-MPG rated car might deliver 22 MPG in city traffic or 28 MPG on the highway. This calculator captures your actual numbers.
Fleet tracking and efficiency improvement: Miami fleets track 18 MPG across 50 vans to identify underperformers. Austin agencies compare 28 MPG across employee vehicles for $500 monthly fuel budgets. Chicago logistics firms average MPG across 100 trucks for $20,000 monthly fuel costs. Denver mining companies track 12 MPG for heavy equipment fleets. Seattle delivery services compare 25 MPG across vans. New York taxi companies monitor 20 MPG across 200 cabs. The tool is free, works instantly offline, and requires no signup ever.
Where it is used
Austin commuters computing 28 MPG for 300-mile $42 commutes from Round Rock to downtown at $3.50 per gallon, Chicago rideshare drivers tracking 22 MPG for 150-mile $24 airport runs at $3.80 per gallon, Miami delivery fleets measuring 18 MPG for 200-mile $40 routes at $3.60 per gallon, Denver truckers calculating 12 MPG for 500-mile $150 hauls at $3.75 per gallon, Seattle delivery vans computing 25 MPG for 100-mile $14 routes at $4.00 per gallon, and New York taxi fleets tracking 20 MPG for 80-mile $16 daily circuits at $4.20 per gallon.
How to use the Mileage
- Trip Distance — enter the value (e.g. 300).
- Distance Unit — enter the value.
- Fuel Used — enter the value (e.g. 12).
- Fuel Unit — enter the value.
- Fuel Price Per Unit (optional) — enter the value (e.g. 3.50).
- Calculate — press the Calculate button to see the result instantly above.
Formula
MPG = miles / gallons. L/100km = 235.214 / MPG. Cost = fuel × price.
Examples
Standard US fill
Metric inputs
No price entered
Frequently Asked Questions
- Why does my MPG differ from the window sticker?
- Sticker ratings use lab cycles. Real driving adds cold starts, idling, hills, cargo, and lead feet, typically 10 to 20 percent below rated.
- How do I convert MPG to L per 100km?
- Divide 235.214 by the MPG figure. A 25 MPG car uses about 9.4 L per 100km.
- Should I use one tank or several?
- Several. Pump shut-off inconsistency adds noise to single fills. Average three or more tanks for a stable figure.
- Does this work for electric vehicles?
- No. This calculator uses fuel volume. For EVs, use a kWh-per-mile calculator instead.
- Is this free and private?
- Yes. It works instantly offline with no signup required ever. No data leaves your browser.
- Can I track fuel cost per mile?
- Yes. Divide trip cost by distance. At $42 for 300 miles, cost per mile is $0.14.