Driving
Annual fuel cost
Annual miles divided by miles per gallon gives gallons, multiplied by the price per gallon.
The Formula
F = D / e x p
Annual miles divided by miles per gallon gives gallons, multiplied by the price per gallon.
| Symbol | Meaning | Unit | Notes |
|---|---|---|---|
| F | Annual fuel cost | USD/year | What the commute costs in fuel over a year. |
| D | Annual miles | miles/year | Distance driven commuting in a year. |
| e | Fuel economy | miles/gal | Real miles per gallon on this route, not the test cycle figure. |
| p | Fuel price | USD/gal | Price per gallon at the pump. |
What Each Symbol Means
FUSD/year
Annual fuel cost
What the commute costs in fuel over a year.
Dmiles/year
Annual miles
Distance driven commuting in a year.
emiles/gal
Fuel economy
Real miles per gallon on this route, not the test cycle figure.
pUSD/gal
Fuel price
Price per gallon at the pump.
See It Worked With Real Numbers
A formula on its own does not tell you which number goes where. The how to calculate commute cost page applies this equation to a concrete case, shows every intermediate step, and names the mistakes that produce a wrong answer even when the algebra is right.
Where This Formula Appears
This equation is the working core of How To Calculate Commute Cost, filed under Everyday Life. Every number the guide produces comes from substituting into this one line.