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$4.27/gal

Cost Per Mile Calculator

⛽
/gal
🚗
MPG

How to Use This Calculator

  1. 1

    Use the MPG you actually get

    Fill the tank, reset the trip meter, and at the next fill divide the miles driven by the gallons added: 330 miles on 11 gallons is 30 MPG. For mostly city driving, the city rating is closer than the highway one.

  2. 2

    Enter maintenance and insurance per mile, not per year

    Divide each yearly cost by the miles you drive in a year. A $1,200 yearly cost over 10,000 miles is $1,200 ÷ 10,000 = $0.12 per mile. Typing 1200 into the field would add $1,200 to every mile.

  3. 3

    Replace the prefilled gas price with what you pay

    The price field starts at an average price. Every 10 cents per gallon changes the cost of a 25 MPG car by 0.4 cents per mile, or $4 per 1,000 miles.

Formula and Logic

Fuel cost per mile is the gas price divided by MPG. Maintenance and insurance are added exactly as you enter them. Nothing else, such as depreciation or loan payments, is included.

Basic fuel cost per mile

Gas price ÷ MPG = fuel cost per mile

Example: $4.00 ÷ 20 MPG = $0.20 per mile

Cost per 100 miles

(100 ÷ MPG) × Gas price = cost per 100 miles

Example: (100 ÷ 20) × $4.00 = $20.00 per 100 miles

Full cost per mile (with advanced inputs)

Fuel per mile + maintenance per mile + insurance per mile = full cost per mile

Example: $0.127 + $0.06 + $0.08 = $0.267 per mile

Example Calculations

Example 1: Fuel cost only

Inputs

  • Gas price$3.50/gal
  • Vehicle MPG25

Outputs

  • Fuel cost per mile$0.140
  • Cost per 100 miles$14.00

$3.50 ÷ 25 = $0.14 per mile. 100 miles uses 4 gallons, so 100 miles costs $14.00.

Example 2: Less efficient vehicle

Inputs

  • Gas price$4.20/gal
  • Vehicle MPG18

Outputs

  • Fuel cost per mile$0.233
  • Cost per 100 miles$23.33

At the same $4.20, a 30 MPG car would cost $0.140 per mile, so this vehicle costs $0.093 more per mile, or $9.33 more per 100 miles.

Example 3: Full cost with maintenance and insurance

Inputs

  • Gas price$3.80/gal
  • Vehicle MPG30
  • Maintenance per mile$0.06
  • Insurance per mile$0.08

Outputs

  • Fuel cost per mile$0.127
  • Full cost per mile$0.267

Fuel is $3.80 ÷ 30 = $0.127 per mile, less than half of the $0.267 full cost once $0.14 of maintenance and insurance is added.

Frequently Asked Questions

How do I calculate gas cost per mile?
Divide the price per gallon by your MPG. At an example price of $3.50 a gallon, a 25 MPG car costs $3.50 ÷ 25 = $0.14 per mile and a 35 MPG car costs $3.50 ÷ 35 = $0.10 per mile.
How much does it cost to drive 100 miles?
Divide 100 by your MPG to get gallons, then multiply by the price. A 25 MPG car uses 4 gallons per 100 miles, which is $14.00 at an example $3.50 a gallon. A 40 MPG car uses 2.5 gallons, or $8.75. The calculator shows this as Cost Per 100 Miles.
How much is 1 extra MPG worth?
More at low MPG than at high MPG. At an example $3.50 a gallon, going from 15 to 16 MPG cuts fuel cost from $0.233 to $0.219 per mile, about 1.5 cents, or $175 over 12,000 miles. Going from 40 to 41 MPG saves only about 0.2 cents a mile, about $26 over 12,000 miles.
Should I enter city, highway or combined MPG?
Enter the MPG you actually get on the miles you are costing. For a car rated 28 MPG city and 36 MPG highway, at an example $3.50 a gallon the city figure gives $0.125 per mile and the highway figure $0.097. That 2.8 cent gap is about $333 over 12,000 miles, so picking the wrong one matters.
What does the full cost per mile include?
Fuel cost per mile plus the maintenance and insurance amounts you enter, nothing else. It leaves out depreciation, registration, loan interest, parking and tolls. Example: $3.50 ÷ 25 MPG = $0.14 for fuel, plus $0.06 maintenance and $0.08 insurance, gives $0.28 per mile.
How do I turn yearly maintenance or insurance costs into a per mile figure?
Divide the yearly cost by the miles you drive in a year. $900 of maintenance over 12,000 miles is $900 ÷ 12,000 = $0.075 per mile. A fixed yearly premium costs more per mile the less you drive: $1,500 of insurance is $0.125 per mile at 12,000 miles but $0.25 per mile at 6,000 miles.
How does fuel cost per mile compare with the 2026 IRS mileage rate?
The 2026 IRS business standard mileage rate is $0.725 per mile for miles driven January to June and $0.76 from July 1. It is based on the fixed and variable costs of operating a car, such as depreciation, insurance and repairs as well as fuel, so it is not a fuel cost. A 25 MPG car at an example $3.50 a gallon spends $0.14 per mile on fuel, about 19% of the first rate and 18% of the second.

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Gas Cost CalculatorCommute Cost CalculatorMileage Reimbursement CalculatorIRS Mileage Rate 2026Fuel Savings Calculator