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Fuel CostCalculator

Find out exactly how much your trip will cost in fuel. Calculate monthly fuel bills, compare two vehicles side by side, and discover how much you could save.

100% Free MPG · L/100km · km/L Round Trip Option Vehicle Comparison Monthly & Annual Cost
Fuel Cost Calculator
⛽ Instant Results
Trip Distance
Fuel Price
Fuel Efficiency
Currency
⚠ Please enter valid distance, fuel price, and efficiency values.
Total Fuel Cost
0
Fuel Used
0
Cost / km
0
Total Distance
$3,000
Avg. Annual US Fuel Spend
10 L
Avg. Car per 100 km
3%
Fuel Saved with Proper Tyre Pressure
40%
MPG Gain Fixing O2 Sensor
How It Works

Three Modes, Total Fuel Clarity

Pick the tab that matches your question — from a one-off trip cost to a full annual fuel budget with vehicle comparison.

01
Enter Distance

Type your trip distance in kilometres or miles. Enable round trip to automatically double the distance.

02
Enter Fuel Price

Enter your local fuel price per litre or per gallon. Supports multiple currencies including USD, GBP, EUR, and PKR.

03
Enter Efficiency

Use your car's fuel rating in L/100km, MPG, or km/L. Check your vehicle's manual or fuel display for this value.

04
Read Clear Results

Instantly see total fuel cost, litres used, cost per km, and — in Monthly mode — weekly, monthly, and annual projections.

Road Trip Fuel Planning
📷 Suggested image: A car on an open highway at sunrise — reinforces the trip fuel cost calculation concept and evokes road trip planning.
Fuel Pump & Price Display
📷 Suggested image: A close-up of a fuel pump nozzle with a digital price display — visually anchors the fuel price input and calculator purpose.
The Formula

How Fuel Cost Is Calculated

Three simple variables determine your fuel cost. Our calculator handles any unit combination automatically.

Using L/100km
Cost = (Distance ÷ 100) × Efficiency × Price/L
300km ÷ 100 × 10L × $1.80 = $54.00
Using MPG
Cost = (Distance ÷ MPG) × Price/gallon
200mi ÷ 30mpg × $3.50 = $23.33
Using km/L
Cost = (Distance ÷ km/L) × Price/L
300km ÷ 12 × $1.80 = $45.00
Reference Guide

Typical Fuel Consumption by Vehicle Type

Not sure what fuel efficiency to enter? Use these typical averages as a starting point for your calculation.

Vehicle Type L/100km MPG (US) km/L Monthly Cost* Annual Cost*
Small Hatchback5–734–4714–20$135–$189$1,620–$2,268
Mid-size Sedan7–926–3411–14$189–$243$2,268–$2,916
SUV / Crossover9–1220–268–11$243–$324$2,916–$3,888
Large SUV / Truck12–1615–206–8$324–$432$3,888–$5,184
Hybrid Sedan4–639–5917–25$108–$162$1,296–$1,944
Plug-in Hybrid2–547–11820–50$54–$135$648–$1,620
Motorbike / Scooter3–547–7820–33$81–$135$972–$1,620

*Assumes 1,500 km/month and $1.80/L fuel price. Actual costs vary by region, driving style, and conditions.

Who Uses This Tool

Real World Use Cases

From daily commuters to long-haul truckers, anyone who drives can benefit from knowing their true fuel cost.

Daily Commuters

Calculate your exact weekly and monthly fuel cost. See how much you spend on commuting every year — the number is usually eye-opening.

Road Trip Planning

Budget your fuel cost before you leave. Enter the total route distance and your car's fuel rating to know exactly how much cash to bring.

Logistics & Fleets

Trucking companies and delivery businesses use fuel cost calculators to price routes accurately and keep operating margins in check.

Car Buyers

Use the Compare Vehicles tab to see the real annual fuel cost difference between two cars before making a purchase decision.

Ride-share Drivers

Calculate fuel cost per trip and per km to ensure your per-mile rate covers your actual fuel expenses and remains profitable.

Budget Planners

Include your accurate annual fuel cost in your household budget to see the full picture of your transport spending.

Compare Your Car vs. a Hybrid
📷 Suggested image: Two cars side by side — a traditional sedan and a hybrid — with fuel gauge indicators shown, illustrating the vehicle comparison mode of the calculator.
Save More

Proven Ways to Reduce Fuel Costs

Small changes to your driving habits and vehicle maintenance can cut your fuel bill by 10–40%. Here are the most effective strategies.

01
Check Tyre Pressure

Under-inflated tyres increase rolling resistance. Keeping tyres at the correct pressure reduces fuel use by up to 3%. Check monthly — tyres lose roughly 1 PSI per month.

02
Drive Smoothly

Aggressive acceleration and hard braking waste significant fuel. Smooth, gradual acceleration and anticipating stops ahead can improve fuel efficiency by 10–20%.

03
Maintain Steady Speed

Highway driving at a consistent 90–100 km/h uses considerably less fuel than stop-start city driving. Use cruise control on long stretches to maintain optimal efficiency.

04
Service Your Engine

A properly tuned engine runs more efficiently. Replacing a faulty oxygen sensor alone can improve fuel mileage by up to 40%. Regular oil changes also matter.

05
Plan Your Route

Shorter routes and those with fewer stops use less fuel. Avoid peak traffic hours when possible — idling in traffic burns fuel with zero progress.

06
Reduce Unnecessary Load

Every extra 50 kg in your car increases fuel use by about 1–2%. Clear out heavy items from the boot that you don't need for the trip.

What Is a Fuel Cost Calculator?

A fuel cost calculator is a free online tool that estimates how much money you will spend on petrol or diesel for any given journey, based on three simple inputs: the distance you intend to travel, your vehicle's fuel efficiency rating, and the current price of fuel in your area. Instead of rough guesses, you get a precise number — calculated instantly and displayed in a format you can actually use for budgeting and planning.

This improved calculator goes beyond a basic trip estimator. It offers three distinct modes: a Trip Cost calculator for one-off journeys, a Monthly and Annual Cost calculator for budgeting your regular driving expenses, and a Vehicle Comparison tool that shows you the real-world fuel cost difference between two cars side by side.

How to Calculate Fuel Cost for a Trip — Step by Step

Step 1: Know Your Distance

Start by finding the actual driving distance of your route — not a straight-line estimate. Use a mapping app (Google Maps, Waze, or similar) to get the road distance. For a round trip, simply enable the "Round trip" toggle and the calculator doubles the distance automatically.

Step 2: Know Your Fuel Price

Enter the current price of fuel at the pump near your starting point. If you're unsure, check a local fuel price app or petrol station website. Enter the price per litre (L) or per gallon (US or UK) depending on your region.

Step 3: Know Your Vehicle's Fuel Efficiency

This is your car's consumption rate — how much fuel it uses over a given distance. You'll find this in your vehicle's specifications, owner's manual, or on the manufacturer's website. This calculator accepts three common units:

  • L/100km — litres per 100 kilometres (used in most of Europe, Australia, Canada)
  • MPG — miles per gallon (US and UK standard)
  • km/L — kilometres per litre (common in Japan, India, parts of Asia)

Real-world vs. rated efficiency: Manufacturers' official fuel ratings are tested under controlled conditions. In real driving — with traffic, air conditioning, and varying speeds — you'll typically achieve 10–20% worse efficiency than the rated figure. Use your own observed fuel consumption for the most accurate result.

📌 Worked Example — Sydney to Melbourne Road Trip

Distance: 878 km one way (1,756 km return). Vehicle: Toyota RAV4 at 8.5 L/100km. Fuel price: $2.10/L.

Calculation: (1,756 ÷ 100) × 8.5 × $2.10

= $313.38 round trip fuel cost

Understanding Fuel Efficiency Units — L/100km vs MPG vs km/L

One of the most confusing aspects of fuel cost calculations is the variety of efficiency units used around the world. Here's how they relate:

L/100km (Litres per 100 Kilometres)

This is a consumption rate — lower is better. A car rated at 6 L/100km is more fuel-efficient than one rated at 12 L/100km. This unit is standard in most of Europe, Australia, Canada, and many Asian countries. Formula: L/100km = Litres ÷ (km ÷ 100)

MPG (Miles per Gallon)

This is an efficiency rate — higher is better. A car getting 40 MPG is more efficient than one getting 20 MPG. Note that US gallons (3.785 L) and UK imperial gallons (4.546 L) differ significantly, meaning US and UK MPG figures are not directly comparable. To convert: L/100km = 235.214 ÷ MPG (US)

km/L (Kilometres per Litre)

An efficiency rate — higher is better. Commonly used in Japan, India, and parts of Southeast Asia. Simple conversion: km/L = 100 ÷ L/100km. A car rated at 14 km/L is equivalent to 7.14 L/100km.

When comparing vehicles: Always use the same unit for both cars. Our Vehicle Comparison tab accepts different units per vehicle and converts them automatically, so you never need to do the maths manually.

What Factors Drive Fuel Costs Up or Down?

Vehicle Age and Engine Condition

Older vehicles with worn engines, dirty fuel injectors, or failing sensors consume more fuel than their rated efficiency suggests. Regular servicing — particularly fixing emission sensors and replacing air filters — can restore a significant portion of lost efficiency.

Driving Speed

Aerodynamic drag increases exponentially with speed. Most vehicles reach their peak fuel efficiency between 80–100 km/h (50–62 mph). Driving at 120 km/h versus 90 km/h can increase fuel consumption by 20–25%.

Load and Cargo

A heavier vehicle requires more energy to accelerate. An extra 100 kg increases fuel consumption by approximately 3–7%, depending on the vehicle. Roof racks and cargo boxes add aerodynamic drag even when empty.

Air Conditioning

Running air conditioning at full capacity increases fuel consumption by 5–15%, particularly in stop-start city traffic. On cool days or at lower speeds, opening windows is more fuel-efficient.

Fuel Quality

Using the manufacturer's recommended fuel grade matters. Using a lower octane fuel than required in a high-performance engine can cause knock, reduce efficiency, and increase wear over time.

Monthly and Annual Fuel Cost — Why It Matters

Most drivers think about fuel in terms of individual fill-ups, but the annual picture is far more revealing. The average American driver spends approximately $3,000 per year on fuel. In the UK, with higher petrol prices, the figure is often £2,000–£3,500. That's a significant household expense — and one that varies enormously based on your vehicle choice.

The difference in annual fuel cost between a large SUV (12 L/100km) and a compact hybrid (5 L/100km) at 1,500 km/month and $1.80/L is $1,458 per year. Over five years, that's $7,290 — which is often larger than the price difference between the two vehicles. Use the Monthly/Annual tab to see your personal numbers.

FAQ

Frequently Asked Questions

Quick answers to the most common questions about calculating fuel costs and fuel efficiency.

How do I calculate fuel cost for a trip?

The formula is: Fuel Cost = (Distance ÷ 100) × Fuel Consumption Rate × Price per Litre. For example, a 300 km trip in a car using 10 L/100km with fuel at $1.80/L costs (300 ÷ 100) × 10 × $1.80 = $54.00. Enter your values in the Trip Cost tab above and the calculator does this instantly.

How many litres of fuel does it take to drive 100 km?

This depends entirely on your vehicle. A small hatchback typically uses 5–7 litres per 100 km. A mid-size sedan uses 7–9 L/100km. An SUV uses 9–14 L/100km. A large pickup truck or diesel van may use 14–20 L/100km. Check your vehicle's manual or use the reference table on this page for typical values by vehicle type.

How do I convert MPG to L/100km?

To convert US MPG to L/100km, divide 235.214 by the MPG figure. For example, 30 MPG = 235.214 ÷ 30 = 7.84 L/100km. To convert UK MPG (imperial gallons), divide 282.48 by the MPG figure. Our calculator accepts all three units and converts automatically — you never need to do this manually.

What is a good fuel consumption rate for a car?

For a petrol car, under 7 L/100km (over 33 MPG) is considered good. Under 6 L/100km is excellent. Over 10 L/100km is poor efficiency. Diesel engines are typically 20–25% more efficient than equivalent petrol engines. Hybrids can achieve 4–6 L/100km in mixed driving, and plug-in hybrids can go even lower if regularly charged.

How much does fuel cost per month for an average driver?

The average driver covers around 1,200–1,500 km per month. At 10 L/100km and $1.80/L, that works out to approximately $216–$270 per month, or $2,592–$3,240 per year. Use the Monthly / Annual tab above to enter your exact distance and local fuel price for a personalised estimate.

Is this fuel cost calculator free?

Yes — completely free, forever. No account required, no ads blocking your results, no subscription. SpeedCalculator.net is a free tool available to everyone with no usage limits.

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