Fuel Cost Calculator – Estimate Trip Fuel & Price

Todd Mitchell (photo)
By Todd Mitchell
On: Sunday, June 7, 2026 10:10 PM
fuel cost

Fuel Cost Calculator

Instantly estimate the fuel cost of any trip — enter your distance, fuel economy, and local price.

Fuel Cost Calculator

Distance · Economy · Price

km or miles
in selected unit
Fuel Used
Total Cost
Cost per km/mile

How It Works

The calculator converts your fuel economy to litres used per distance unit, multiplies by total distance, then multiplies by fuel price. Unit conversions are handled internally.

Litres used = Distance × (Consumption in L/100km ÷ 100) | Total Cost = Litres × Price per Litre

How to Use This Calculator

  1. Enter the one-way or round-trip distance.
  2. Select your fuel economy unit and enter the value.
  3. Enter the local fuel price per litre (or gallon for MPG).
  4. Click Calculate — see total litres and cost.
  5. Adjust the economy value to compare two vehicles.

Worked Example

Example: 500 km at 8.0 L/100km with fuel at $1.65/L → 40 L used × $1.65 = $66.00 total trip cost.

Reference Table

Economykm/LL/100kmMPG US
Excellent (HEV)254.058.8
Very Good185.642.3
Good147.133.0
Average128.328.2
Below average1010.023.5
SUV typical812.518.8
Truck typical616.714.1

Frequently Asked Questions

How do I convert MPG to L/100km?

Divide 235.2 by your MPG figure. So 30 MPG equals 235.2÷30 = 7.84 L/100km. This inverse relationship means better fuel economy is a lower L/100km number.

What fuel price should I enter — per litre or per gallon?

Match the price unit to your economy unit. If you're using L/100km or km/L, enter price per litre. If using MPG US or MPG UK, enter price per US or UK gallon respectively.

Why does my fuel cost calculation differ from my actual receipt?

Real-world factors include: driving style (aggressive acceleration can add 20–30%), AC use, tyre pressure, wind, and altitude. The calculator gives a baseline for typical conditions.

How accurate is the fuel cost estimate for long road trips?

Accuracy is typically ±10–15% of real cost when you use a realistic economy figure from your trip computer. Highway fuel economy is usually 10–20% better than city.

Can this calculator handle electric vehicle running costs?

For EVs use our separate EV vs Gas Cost Calculator which takes kWh/100km and electricity price as inputs.