How to Calculate MPG
The formula is simple: MPG = Miles Driven / Gallons Used. Fill up your tank, reset the trip odometer, drive normally, then fill up again. The gallons on the second fill-up divided into the miles driven gives you MPG.
Average MPG by Vehicle Type
| Vehicle Type | City MPG | Highway MPG | Combined |
|---|---|---|---|
| Compact Car | 28-32 | 35-42 | 30-36 |
| Mid-size Sedan | 25-30 | 32-38 | 28-33 |
| SUV / Crossover | 20-26 | 26-32 | 22-28 |
| Full-size Truck | 15-20 | 20-26 | 17-22 |
| Hybrid | 45-55 | 42-50 | 44-52 |
| Minivan | 18-22 | 26-30 | 21-25 |
Tips to Improve Your MPG
- Check tire pressure monthly— underinflated tires can reduce MPG by 2-3%. The correct pressure is on the driver's door jamb sticker, not the tire sidewall.
- Remove excess weight — every 100 lbs reduces MPG by about 1%. Clean out the trunk.
- Use cruise control on highways — maintaining steady speed is more efficient than accelerating and braking.
- Avoid aggressive driving — rapid acceleration and hard braking can lower MPG by 15-30% on the highway.
- Keep up with maintenance — dirty air filters, old spark plugs, and low oil can all reduce fuel efficiency.
FAQ
Why is my real MPG lower than the EPA rating?
EPA tests are done in controlled lab conditions. Real-world factors like traffic, weather, terrain, driving style, and AC use all reduce actual MPG. Most drivers get 10-20% less than the EPA combined rating.
How do I convert MPG to L/100km?
Divide 235.215 by your MPG. For example, 30 MPG = 235.215 / 30 = 7.84 L/100km. Our calculator does this automatically.