Free to use, no account
Fuel Economy Calculator
Measure what your vehicle actually uses. Add each complete full-to-full refill to compare fuel economy and cost over time.
History stays in this tab only, up to 100 entries. It is not saved automatically. Use one currency for all entries; it stays locked while entries remain.
Your results
- Total distance
- Total fuel
- Total cost
| Date | Distance | Fuel | Cost | L/100 km | Cost/km | Remove |
|---|
No refills logged yet.
This is a calculation from your entries, not an official vehicle rating. Odometer readings, pump shut-off, terrain, traffic, weather, load, driving style and fuel type can change real-world results.
How do I calculate fuel economy from a refill?
Enter the distance driven since the previous full tank, the fuel added at this refill and the total price paid. For a useful result, start and end each interval with a full tank. The calculator converts the same entry to L/100 km, km/L, US MPG and imperial MPG.
Frequently asked questions
How do I calculate fuel economy from a refill?
Enter the distance driven since the previous full tank, the fuel added at this refill and the total price paid. For a useful result, start and end each interval with a full tank. The calculator converts the same entry to L/100 km, km/L, US MPG and imperial MPG.
Does the fuel log leave this page?
No. Entries stay in this browser tab and are cleared when you clear them or close the page. Export a CSV yourself if you want a separate copy. No account, upload or fuel-price service is used.
What does L/100 km mean?
It is the litres of fuel used to travel 100 kilometres. A lower number means less fuel for the same distance.
How do I convert fuel economy to US MPG?
Choose the distance and fuel units for your entry. The calculator converts the same measured interval to US MPG and imperial MPG; those gallon sizes are different.
Why should I use full-to-full refills?
Starting and ending with a full tank makes the fuel added a closer measure of what was used over that distance. One partial refill can make an interval less accurate.