Fuel Cost Calculator
Work out how much fuel a journey will cost. Enter your distance, your vehicle's MPG or L/100km, and the price of fuel to get the total cost, litres or gallons needed, and cost per mile — with miles/km and gallon/litre support.
How to use this tool
Enter Trip Distance
Type your journey distance and pick miles or kilometres. Toggle Round Trip to double it automatically.
Set Fuel Efficiency
Enter your vehicle's economy in MPG, km/L, or L/100km — whichever your dashboard or manual uses.
Add Fuel Price
Enter the price per gallon or litre. The tool returns total cost, fuel needed, and cost per mile or km instantly.
Driving with friends? Divide the total cost by the number of passengers to split fuel fairly for road trips and carpools.
Plan Your Budget
Knowing the fuel cost before a trip helps you compare routes, split costs with passengers, and decide whether driving beats other transport.
Efficiency Matters
A small gain in fuel economy compounds over thousands of miles. Smooth driving and correct tyre pressure can cut your fuel bill noticeably.
Know the Cost Before You Drive
Fuel is one of the largest variable costs of owning a car, yet most people only find out what a journey cost after they've paid at the pump. This fuel cost calculator flips that around: enter your distance, your vehicle's efficiency, and the current fuel price, and you'll instantly see the total cost, how much fuel you'll burn, and the cost per mile or kilometre. It works for cars, vans, motorbikes and trucks, in miles or kilometres, and with gallons or litres — so it's useful wherever you are in the world.
The Simple Formula Behind It
Every fuel cost estimate comes down to two steps:
Fuel needed = Distance ÷ Efficiency Total cost = Fuel needed × Fuel price
For example, a 300-mile drive in a car that does 30 MPG needs 300 ÷ 30 = 10 gallons. At $3.50 per gallon, that's 10 × $3.50 = $35. The calculator runs this for you and converts between units automatically, so you can mix miles with litres or kilometres with gallons without doing the maths by hand.
Understanding Fuel Efficiency Units
Different countries measure economy differently, which is a common source of confusion:
- MPG (miles per gallon) — used in the US and UK. Higher is better.
- km/L (kilometres per litre) — common in parts of Asia and the Middle East. Higher is better.
- L/100km (litres per 100 km) — used across Europe. Lower is better.
As a rough guide, 30 MPG is about 7.8 L/100km or roughly 12.7 km/L. The calculator accepts all three, so just enter whichever figure your dashboard or owner's manual shows.
A Worked Example: Planning a Weekend Road Trip
Suppose you're driving 220 km each way to visit family, your car does 6.5 L/100km, and fuel is priced per litre. Switch the tool to kilometres and L/100km, enable Round Trip, and enter your local fuel price. The total distance becomes 440 km, the fuel needed is about 28.6 litres, and the cost is calculated at your exact pump price. You instantly see whether driving is cheaper than the train — and what each passenger owes if you split it.
US Gallons vs UK Gallons
One important detail: this tool uses the US gallon (3.785 litres). The UK imperial gallon is larger at 4.546 litres, which is why UK cars appear to have higher MPG figures for the same real-world economy. If you're in the UK or anywhere that prices fuel by the litre, the most accurate approach is to switch the price unit to litres and your economy to km/L or L/100km.
Smart Ways to Cut Your Fuel Bill
- Ease off the pedal: aggressive acceleration and braking can raise consumption by 15–30% on the highway.
- Check your tyres: under-inflated tyres increase rolling resistance and waste fuel.
- Lose dead weight: roof boxes and a loaded boot hurt aerodynamics and economy.
- Combine trips: a warm engine is far more efficient than several cold starts.
Why Use This Calculator
Whether you're budgeting a commute, comparing two routes, pricing a delivery, or splitting costs with friends, an accurate fuel estimate saves money and removes guesswork. Bookmark this tool, and pair it with the percentage calculator to work out savings, or the car loan vs lease calculator when weighing the full cost of running a vehicle.