MPG Calculator
Curious what mileage you actually got on your last trip? Enter your miles driven and gallons used below to find out.
Enter your trip details
Find out what mileage you actually got, after the fact.
Your results
Real-world MPG normally runs a bit below a vehicle's rated figure, especially with highway speeds, AC use, cargo weight, or a lot of stop-and-go driving.
This is a simple average based on the numbers you entered and does not account for partial fill-ups, fuel left in the tank, or pump inaccuracies. For the most accurate figure, fill the tank completely at both the start and end of your measured mileage.
How It Works
Add up how many miles you drove, either your trip odometer or the difference between your starting and ending mileage, then enter how many gallons it took to fill the tank back up. The calculator divides the two to give you your real-world miles per gallon. If you know what you paid at the pump, add that too for your cost per mile and total fuel spent on the trip. And if you know your vehicle’s rated MPG from the window sticker or owner’s manual, enter that as well to see exactly how your actual mileage compares, whether you beat the rating or fell short of it.
Why It’s Useful
The MPG rating on a new car’s window sticker is a lab estimate, not a guarantee, real mileage depends on how and where you actually drive. Highway cruising, city stop-and-go, a loaded-down trunk, running the AC, and even tire pressure can all move the number up or down. Tracking your actual MPG after a trip gives you a real number to work with instead of a manufacturer’s estimate: useful for spotting a developing mechanical issue, comparing mileage between two different routes or driving styles, or just getting an honest read on your fuel costs for regular trip planning.
Keep in mind this is a simple average based on the numbers you enter. For the most accurate reading, fill your tank completely both before and after the mileage you’re measuring, a partial fill-up will throw the number off.