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Fuel Cost Calculator

Estimate trip fuel and cost using metric, US or independently selected units for distance, fuel economy and pump price.

Currency: USD

Enter all amounts in USD. Changing currency keeps numbers unchanged; no exchange rate is applied.

Your inputs

Calculations run in your browser. No account needed.

EXAMPLE RESULTCalculated locally
Fuel needed
35 L
Fuel cost
$52.50
Clear inputs. Transparent methods.
My workspace

Calculate with your inputs to save a result or compare scenarios.

How it works

A useful distinction

Mileage gains and savings differ

Improving from 20 to 25 mpg is a 25% mileage gain but a 20% fuel-cost reduction for the same trip and pump price. Compare calculated trip costs rather than treating the mpg percentage as the saving.

Estimating a trip's fuel spending

A fuel-cost estimate combines trip distance, fuel economy, and the price per fuel unit. Check whether consumption is expressed as distance per fuel amount or fuel amount per distance, because those conventions move in opposite directions. Use the independent-units mode when the inputs come from different systems. Actual traffic, route conditions, and driving can differ from the average consumption entered.

Metric trip: formula and assumptions

Liters = distance×consumption/100. Cost = liters×price.

Actual consumption depends on speed, load, terrain, weather, and driving conditions.

US trip: formula and assumptions

Gallons = miles/mpg. Cost = gallons×price.

This mode uses US gallons.

Trip with independent units: formula and assumptions

Fuel liters = distance(km) × liters per kilometer; cost = liters × price per liter.

Distance, fuel economy, and pump price use independently selected units. Currency is a label only; this tool does not convert currencies.

Worked example

Reference example currency: USD. These fixed examples do not change with your calculator preferences.

Using the Metric trip example:

Inputs
Distance (km)
500
Fuel consumption (L/100 km)
7
Fuel price (per liter)
1.5
Method

Liters = distance×consumption/100. Cost = liters×price.

Result

Example result

Fuel needed: 35 L

Fuel cost: $52.50

These are illustrative inputs. Change the values to explore a different scenario.

Formula references

References explain the underlying methods; they do not imply endorsement or individual professional review of Finflo.

Common questions

Can the distance unit differ from the fuel-price unit?

Yes. Mixed-units mode converts the distance, economy and pump-price units independently before calculating fuel use and cost.

Does choosing a currency convert the fuel price?

No. Currency is a label in this tool. Enter a pump price expressed in the currency you want the cost to use.

Prepared by Finflo. See our methodology and editorial policy.