Fuel Cost Calculator
Enter your route distance, efficiency and fuel price, then set annual trips and people sharing the trip. Optional second-vehicle efficiency uses the same selected unit. Known-quantity cost = supplied liters × supplied price per liter. The quantity already covers the trip you name; no distance, efficiency, return multiplier or second-vehicle estimate is used. Yearly, monthly and shared costs still use the entered trips and people.
Estimated trip fuel
Fuel per trip:
Cost per trip:
Average monthly cost (year ÷ 12):
Yearly cost:
Cost per person per trip:
Second vehicle cost per trip:
Second vehicle yearly cost:
Yearly saving (first − second):
A negative saving means the second vehicle costs more. This estimate excludes other vehicle and travel costs.
A QUICK WALKTHROUGH
How to use this tool
- Set distance, units and optional round trip.
- Enter efficiency, fuel price, currency, yearly trips and people; optionally add a second efficiency.
- Calculate and review fuel, trip, average monthly, annual, person and comparison estimates.
Formula and rounding
Fuel = km × L/100 km ÷ 100, or miles ÷ mpg × gallon litres. 1 mi = 1.609344 km; US gallon = 3.785411784 L; UK gallon = 4.54609 L. Cost = litres × price per litre; yearly = trip cost × trips; monthly = yearly ÷ 12 (average); per person = trip cost ÷ people. Calculations use unrounded values; ordinary displays round to 2 decimals, even for currencies with different minor units. Nonzero results below 0.005 in magnitude use scientific notation with up to 2 decimal places in the mantissa, preserving the sign of small savings. If currency-style formatting is unavailable, the ISO code prefixes the number. Values that overflow or underflow to zero during calculation are rejected.
Display currency (no conversion)
Currency only labels your entered price; it does not exchange money. Available ISO currency codes and names depend on your browser. Fallback: USD, EUR, GBP, CNY, JPY, KRW, PHP, INR; code labels are used if names are unavailable.
Second vehicle efficiency (optional, same selected unit)
Compare using the same distance, round-trip choice, annual trips and fuel price. Presets are illustrative numbers, not real vehicle specifications. A negative saving means the second vehicle costs more. This estimate excludes other vehicle and travel costs.
Estimated trip fuel
Enter your own fuel efficiency and price. This calculator does not fetch live fuel prices or vehicle data. Inputs stay in this browser and are calculated locally.
Known fuel quantity
Known-quantity cost = supplied liters × supplied price per liter. The quantity already covers the trip you name; no distance, efficiency, return multiplier or second-vehicle estimate is used. Yearly, monthly and shared costs still use the entered trips and people. Direct example: 18 L × 1.25 per L = 22.5 in the entered currency per trip. Values illustrate arithmetic, not price or consumption advice.
GOOD TO KNOW
Common questions
Does changing currency convert the fuel price?
No. Currency only labels the entered number. Enter a price already expressed in that currency.
What does a negative saving mean?
The second vehicle has a higher annual fuel cost under the same trip assumptions.