Mileage Calculator — Distance Between Trips
Calculate trip distance and fuel efficiency from odometer readings. See also Gas Mileage Calculator and Fuel Cost Calculator.
How to Calculate Mileage and Fuel Efficiency
1. Record your odometer reading when you fill up your tank (starting odometer). 2. Drive normally until your next fill-up. 3. Record the new odometer reading (ending odometer) and how much fuel you added. 4. Subtract starting from ending odometer to get distance driven. 5. Divide distance by fuel used to get miles per gallon (MPG).
Mileage Formula
Distance = Ending Odometer - Starting Odometer
MPG = Distance (miles) / Fuel Used (gallons)
km/L = Distance (km) / Fuel Used (liters)
L/100km = (Fuel Used (L) / Distance (km)) x 100
Cost per Mile = (Fuel Price x Gallons) / Distance
Example
Trip: Start 45,000 mi, End 45,350 mi, Used 12 gallons:
Distance = 45,350 - 45,000 = 350 miles
MPG = 350 / 12 = 29.2 MPG
L/100km = (45.42 L / 563.3 km) x 100 = 8.1 L/100km
At $3.50/gal: Cost per mile = $0.12
MPG to L/100km Conversion Table
| MPG | L/100km | km/L |
|---|---|---|
| 15 | 15.7 | 6.4 |
| 18 | 13.1 | 7.7 |
| 20 | 11.8 | 8.5 |
| 22 | 10.7 | 9.4 |
| 25 | 9.4 | 10.6 |
| 28 | 8.4 | 11.9 |
| 30 | 7.8 | 12.8 |
| 33 | 7.1 | 14.0 |
| 35 | 6.7 | 14.9 |
| 40 | 5.9 | 17.0 |
| 45 | 5.2 | 19.1 |
| 50 | 4.7 | 21.3 |
Frequently Asked Questions
What is a good MPG for a car?
Average fuel economy for new cars is about 25-30 MPG combined. Hybrids achieve 40-60 MPG, while trucks and SUVs typically get 15-25 MPG. Above 30 MPG is considered good for a non-hybrid.
How do I convert MPG to L/100km?
Divide 235.215 by the MPG value. For example, 30 MPG = 235.215 / 30 = 7.8 L/100km. Lower L/100km means better fuel efficiency.
Why does my MPG vary between trips?
MPG varies due to driving conditions (city vs highway), speed, weather, tire pressure, cargo weight, and driving style. Highway driving at steady speeds gives the best MPG.
Should I use the trip odometer or main odometer?
Either works. The trip odometer is convenient because you can reset it at each fill-up. If using the main odometer, just subtract the previous reading from the current one.
How can I improve my fuel efficiency?
Maintain proper tire pressure, avoid aggressive acceleration, drive at moderate speeds (55-65 mph is optimal), remove excess weight, and keep up with regular maintenance like air filter changes.