The cost of any drive comes down to three numbers: how far you go, how many miles your car gets per gallon, and what you pay at the pump. Divide the distance by your MPG to get gallons, multiply by the price per gallon, and you have the fuel cost. Everything below is that one formula applied to the distances people actually search for.
The formula for driving cost
Fuel cost = (distance ÷ MPG) × price per gallon. A 300-mile drive in a 28-MPG car at $3.50 a gallon burns about 10.7 gallons and costs roughly $37 — about 13 cents a mile. Change any of the three inputs in the gas cost calculator to price your own trip in seconds.
How much does it cost to drive 100 miles?
At an average 25 MPG and $3.50 a gallon, 100 miles burns 4 gallons and costs about $14. A thirsty 18-MPG truck is closer to $19–$20; a 40-MPG hybrid only about $9. Between $3 and $4 a gallon, expect roughly $12–$16 in a typical car.
How much does it cost to drive 500 miles?
Five hundred miles is about 20 gallons at 25 MPG — roughly $60 at $3 a gallon, $70 at $3.50, and $80 at $4. A 40-MPG hybrid halves the gallons to 12.5, or about $44; a 15-MPG SUV pushes it past $115.
How much does it cost to drive 1,000 miles?
At 25 MPG a 1,000-mile trip uses 40 gallons — about $120 at $3, $140 at $3.50, and $160 at $4 a gallon. Efficient cars bring it under $90; a big truck or SUV can top $200. This is the range most long road-trip legs fall into.
Fuel cost by distance and MPG
Total fuel cost at $3.50 a gallon, for three common fuel economies. Read down the column closest to your car:
| Distance | 20 MPG | 28 MPG | 40 MPG |
|---|---|---|---|
| 100 miles | $18 | $13 | $9 |
| 250 miles | $44 | $31 | $22 |
| 500 miles | $88 | $63 | $44 |
| 1,000 miles | $175 | $125 | $88 |
What changes your real cost
The table assumes steady driving and the sticker MPG. In the real world, cold weather, city stop-and-go, highway speeds above 70 mph, a loaded roof rack, and low tire pressure can each pull economy down 10–25% — which raises your cost per mile by the same amount. Premium grades and regional price swings do the rest.