Gas Mileage Calculator
Track your vehicle's real-world gas mileage. Enter your odometer readings at the gas station to calculate your exact MPG and L/100km.
Odometer Tracking
Provide your current and previous odometer numbers.
Calculated Distance:320.0 miles
Miles Per Gallon27.8MPG (US)
Liters per 100km8.5L/100km
Kilometers per Liter11.8km/L
Tip: For best accuracy, fill your tank completely each time.
Table of Contents
Test Scenarios
Load example tracking scenarios to see how the math works.
How to Track Your Gas Mileage
The standard manual tracking procedure.
Relying on your car's digital dash for MPG isn't always perfectly accurate. The gold standard for tracking your own gas mileage requires tracking tank-to-tank.
Step 1: Fill Up and Record
Fill your gas tank completely until the pump clicks off. Write down your current odometer reading (this is your Previous Odometer next time).
Fill your gas tank completely until the pump clicks off. Write down your current odometer reading (this is your Previous Odometer next time).
Step 2: Drive
Drive normally until you need gas again. (You don't have to wait until it's completely empty).
Drive normally until you need gas again. (You don't have to wait until it's completely empty).
Step 3: Fill Up Again and Math
Fill the tank completely again. Note the exact gallons added and your new odometer reading. Subtract the old odometer from the new to get distance, and divide by the gallons added.
Fill the tank completely again. Note the exact gallons added and your new odometer reading. Subtract the old odometer from the new to get distance, and divide by the gallons added.
Performance Variations
Compare your actual calculated mileage against how it would change if you had driven more or fewer miles on the exact same amount of fuel (11.5 gallons).
| Distance Traveled | MPG | L/100km |
|---|---|---|
| -20% Distance (256.0) | 22.3 | 10.6 |
| -10% Distance (288.0) | 25.0 | 9.4 |
| Current (320.0)Actual | 27.8 | 8.5 |
| +10% Distance (352.0) | 30.6 | 7.7 |
| +20% Distance (384.0) | 33.4 | 7.0 |
Frequently Asked Questions
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