Petrol Mileage Calculator
Calculate your car’s fuel efficiency, fuel consumption, and estimated trip fuel cost in seconds.
Why use a petrol mileage calculator?
A petrol mileage calculator helps you understand how efficiently your vehicle uses fuel. Instead of guessing whether your car is doing “good mileage,” you can calculate exact values like km per litre, litres per 100 km, and even cost per kilometre. That means smarter travel planning and better control over monthly fuel expenses.
If you commute daily, drive for work, or are planning a long road trip, tracking mileage gives you practical insights that can save money over time.
How to use this calculator
- Enter the total distance travelled in kilometres.
- Enter how many litres of petrol were consumed over that distance.
- Optionally add your petrol price per litre for cost analysis.
- Optionally add a planned trip distance to estimate future fuel need and cost.
- Click Calculate Mileage to get your full result.
What this petrol mileage calculator shows
1) Fuel efficiency (km/L)
This tells you how many kilometres your car travels on one litre of petrol. Higher is better.
2) Fuel consumption (L/100 km)
This is a standard metric used globally. Lower is better because it means less fuel is needed for every 100 km.
3) MPG (US and UK)
The calculator also converts your mileage into miles per gallon, useful if you compare specs across countries.
4) Cost metrics
If petrol price is provided, you’ll see total fuel cost and cost per kilometre. If planned trip distance is added, you’ll also get projected trip fuel and trip cost.
Formula used
- km per litre = distance (km) ÷ fuel used (L)
- litres per 100 km = (fuel used ÷ distance) × 100
- total fuel cost = fuel used × petrol price
- cost per km = total fuel cost ÷ distance
Factors that affect real-world petrol mileage
Driving style
Aggressive acceleration and hard braking can significantly reduce fuel efficiency.
Traffic conditions
Stop-and-go city traffic usually burns more fuel than steady highway driving.
Tyre pressure and maintenance
Underinflated tyres, dirty air filters, and delayed servicing all increase fuel consumption.
Vehicle load and terrain
Extra weight, roof racks, hills, and rough roads can lower mileage.
Tips to improve petrol mileage
- Keep tyre pressure at recommended levels.
- Drive smoothly and avoid unnecessary rapid acceleration.
- Reduce idling whenever possible.
- Remove excess weight from the boot.
- Service your vehicle regularly and use the recommended engine oil.
- Plan routes to avoid heavy congestion.
Quick example
If you travelled 500 km and used 40 litres of petrol:
- km/L = 500 ÷ 40 = 12.5 km/L
- L/100 km = (40 ÷ 500) × 100 = 8.0 L/100 km
If petrol is 1.80 per litre, total fuel cost is 72.00 and cost per km is 0.144.
Final thoughts
Using a petrol mileage calculator regularly is one of the easiest habits for reducing travel costs. Small efficiency gains—especially for frequent drivers—add up quickly. Save your last results every month and compare trends to spot issues early and keep your car running efficiently.