Fuel Cost Calculator

Q: How do you calculate fuel cost for a trip?

Fuel cost = (Distance ÷ 100) × Fuel Consumption (L/100km) × Price per litre. For example, a 500 km trip in a car using 8 L/100km with fuel at $1.50/L costs: (500÷100) × 8 × 1.50 = $60.

Q: How do you convert L/100km to MPG?

To convert L/100km to US MPG: MPG = 235.21 ÷ (L/100km). For example, 8 L/100km = 235.21 ÷ 8 = 29.4 MPG. To convert MPG to L/100km: L/100km = 235.21 ÷ MPG.

Q: What is considered good fuel economy?

Good fuel economy varies by vehicle type. For passenger cars: under 7 L/100km (over 33 MPG) is excellent, 7–9 L/100km (26–33 MPG) is good, 9–12 L/100km (20–26 MPG) is average. SUVs and trucks naturally consume more fuel.

Q: How much does it cost to drive 100 km?

Cost per 100 km = Fuel Consumption (L/100km) × Price per litre. A car using 8 L/100km with fuel at $1.60/L costs $12.80 per 100 km to run.

Q: How can I reduce my fuel costs?

Key ways to reduce fuel costs: maintain steady speeds and avoid rapid acceleration/braking, keep tires properly inflated (under-inflation increases consumption by 3%), remove excess weight from the vehicle, use cruise control on highways, and service the engine regularly (clean air filters and spark plugs improve efficiency).

What Is a Fuel Cost Calculator?

A fuel cost calculator estimates how much money you will spend on fuel for any trip. You provide the distance, your vehicle's fuel efficiency, and the current fuel price — the calculator does the rest. It is useful for planning road trips, comparing the running costs of different vehicles, and understanding how fuel price changes affect your budget.

How to Use This Fuel Cost Calculator

Enter the trip distance, current fuel price, and your vehicle's fuel efficiency. The calculator instantly shows total fuel cost, total fuel consumed, and cost per kilometre or mile. Toggle between Metric (kilometres and litres) and Imperial (miles and gallons) using the buttons at the top.

To compare two vehicles, enter a second fuel efficiency value in the Vehicle B field. The calculator shows how much you save or spend extra over the trip compared to Vehicle A.

Fuel Cost Formulas

Metric (L/100km)

Fuel Used (L) = Distance (km) ÷ 100 × Efficiency (L/100km)

Total Cost = Fuel Used × Price per Litre

Example: 600 km trip, 7.5 L/100km, fuel at $1.60/L → Fuel = 600÷100×7.5 = 45 L → Cost = 45×1.60 = $72.00

Imperial (MPG)

Fuel Used (gallons) = Distance (miles) ÷ MPG

Total Cost = Fuel Used × Price per Gallon

Example: 400 miles, 32 MPG, fuel at $3.50/gal → Fuel = 400÷32 = 12.5 gal → Cost = 12.5×3.50 = $43.75

Benefits of Calculating Fuel Costs

Plan road trips: Know your fuel budget before you leave, including multiple stops.
Compare vehicles: See real cost differences between your current car and a more efficient model over a year of driving.
Track rising prices: Quickly recalculate how much more a weekly commute costs as fuel prices change.
Evaluate electric vs petrol: Use cost-per-km data to compare EV charging costs with petrol costs.

Frequently Asked Questions

How do you calculate fuel cost for a trip?

Fuel cost = (Distance ÷ 100) × Consumption (L/100km) × Price per litre. A 500 km trip in a car that uses 8 L/100km with fuel at $1.50/L: (500÷100) × 8 × 1.50 = $60.

How do you convert L/100km to MPG?

MPG (US) = 235.21 ÷ L/100km. So 8 L/100km ≈ 29.4 US MPG. To go the other way: L/100km = 235.21 ÷ MPG.

What is considered good fuel economy?

For passenger cars: under 7 L/100km (over 33 MPG) is excellent, 7–9 L/100km (26–33 MPG) is good, 9–12 L/100km (20–26 MPG) is average. Larger SUVs and trucks naturally use more, while hybrids and small cars use less.

How much does it cost to drive 100 km?

Cost per 100 km = Efficiency (L/100km) × Price per litre. At 8 L/100km and $1.60/L, it costs $12.80 per 100 km. This scales linearly with both fuel price and efficiency.

How can I reduce my fuel costs?

Drive at steady speeds (cruise control helps), keep tires inflated to spec (under-inflation raises consumption ~3%), remove roof racks when not in use, avoid idling, and service your engine regularly. Smooth braking and acceleration is the single biggest factor under your control.