Enter your gas price and your car's fuel efficiency to get the fuel cost per
mile. Add your annual mileage for a full yearly fuel budget. The formula is
simple — price ÷ MPG — and the result only depends
on two numbers you already know.
Fuel cost per mile·Annual gallons & annual fuel cost·Updates as you type
Fuel cost only
This calculator covers fuel cost per mile only — it does not include
depreciation, insurance, maintenance, tires, or registration. The IRS mileage rate
(67¢/mile for 2024) is a common proxy for total cost per mile, but fuel
is typically 10–20¢ of that depending on your car's efficiency. Use this tool
to isolate the fuel line item.
Enter your gas price and MPG. Optionally add annual miles for a full yearly fuel cost estimate. Results update as you type.
Use the current price at your usual station.
Your car's real-world average beats the window-sticker figure.
Leave blank to skip the annual cost output.
Gas price
Fuel efficiency
Cost per mile
Annual gallons
Annual fuel cost
The math, honestly
How cost per mile is calculated
The core formula:cost per mile = gas price ÷ MPG.
At $3.50 per gallon and 30 MPG, that's 3.50 ÷ 30 = $0.117 per mile
(approximately). The logic: if your car travels 30 miles on one gallon, and that gallon
costs $3.50, then each of those 30 miles costs $3.50 ÷ 30.
Annual fuel cost follows directly. First, find
annual gallons: annual miles ÷ MPG. At 12,000
miles and 30 MPG that's 12,000 ÷ 30 = 400 gallons. Then multiply
by the gas price: 400 × $3.50 = $1,400 per year. Equivalently,
annual fuel cost = cost per mile × annual miles — both routes
give the same answer.
What moves the needle: both inputs scale the result linearly. Double
the gas price and the cost per mile doubles. Improve from 25 to 30 MPG and the cost
per mile drops by about 17 percent. Over tens of thousands of miles, a more
efficient car compounds that savings significantly. These figures are
approximate — real-world fuel use varies with speed, terrain, temperature,
and load.
Cost per mile by fuel efficiency
Approximate fuel cost per mile at a few common efficiency levels and gas prices, computed
with the same price ÷ MPG formula the calculator uses. Values are
rounded to the nearest tenth of a cent.
Fuel efficiency
At $3.00 / galcost per mile
At $3.50 / galcost per mile
At $4.00 / galcost per mile
At $4.50 / galcost per mile
20 MPG
$0.150
$0.175
$0.200
$0.225
25 MPG
$0.120
$0.140
$0.160
$0.180
30 MPG
$0.100
$0.117
$0.133
$0.150
35 MPG
$0.086
$0.100
$0.114
$0.129
40 MPG
$0.075
$0.088
$0.100
$0.113
50 MPG
$0.060
$0.070
$0.080
$0.090
Values are approximate and rounded to the nearest tenth of a cent. Computed as price
÷ MPG. Enter your exact numbers above for a precise result.
Reading the result
The cost per mile figure answers a few practical questions once you know what it represents.
Commute cost in 30 seconds
Multiply your one-way commute distance by the cost per mile to get the daily fuel cost one way — double it for the round trip, multiply by working days for a monthly or annual commute bill. At $0.117/mile and a 20-mile one-way commute, that's $2.34 one way, $4.68 per day, about $94 for a 20-working-day month.
Comparing two vehicles
Run the calculator twice — once for each car's MPG at the same gas price — and subtract. The difference, multiplied by your annual miles, is the annual fuel saving from the more efficient vehicle. That figure helps weigh the purchase price premium of a hybrid or more efficient model against concrete yearly savings.
Reimbursement and expense tracking
If you track personal vehicle use for a business or side project, cost per mile gives you the actual fuel component of each trip. The IRS standard rate (67¢/mile for 2024) is a bundled total; if you need to separate out fuel from other costs, this calculator gives you the fuel slice specifically.
Why the number looks small — but adds up
Eleven or twelve cents per mile can feel trivial for a single trip, but at 12,000 miles per year it becomes $1,400 or more. The cost per mile is a rate, not an amount — its impact only becomes visible when multiplied by distance. Use the annual miles field above to see the full yearly figure alongside the per-mile rate.
Cost-per-mile glossary
The terms behind the calculator, in plain English.
Cost per mile
The fuel cost of driving one mile — calculated as gas price divided by MPG. It is a rate (dollars per mile), so you multiply it by any distance to get the fuel cost for that distance. At $0.117 per mile, a 100-mile trip costs approximately $11.70 in fuel.
MPG (miles per gallon)
How far your car travels on one gallon of fuel — the US measure of fuel efficiency, where higher is better. It is the denominator in the cost-per-mile formula, so improving your MPG directly reduces your cost per mile. Use your car's real-world average from the trip computer, not the EPA sticker rating.
Annual gallons
How much fuel your car consumes in a year — calculated as annual miles divided by MPG. At 12,000 miles and 30 MPG, that is 400 gallons per year. Multiply by the gas price to get the annual fuel cost.
Annual fuel cost
The total amount spent on fuel in a year — annual gallons times the price per gallon, or equivalently, cost per mile times annual miles. Both routes give the same answer. It is useful for budgeting and for comparing the yearly savings between two vehicles.
IRS standard mileage rate
A cents-per-mile reimbursement rate published annually by the IRS that covers total vehicle operating costs — fuel, depreciation, insurance, and maintenance bundled together. For 2024 it was 67¢ per mile. This calculator computes fuel cost only, which is one component of that total rate.
Frequently asked
Divide the price of gas per gallon by your car's miles per gallon. At $3.50 per gallon and 30 MPG, the fuel cost per mile is $3.50 ÷ 30 ≈ $0.117. The calculator above does this instantly and also multiplies by your annual miles to give a yearly total.
At a national average of around $3.50 per gallon, a car getting 25 MPG costs roughly $0.14 per mile in fuel. At 35 MPG it drops to about $0.10 per mile. These are fuel-only figures — total cost per mile including depreciation, insurance, and maintenance is considerably higher. Use the calculator with your own numbers for a precise fuel-only figure.
Cost per mile = gas price ÷ MPG. Annual fuel cost = (annual miles ÷ MPG) × gas price. Both formulas are equivalent: cost per mile × annual miles = annual fuel cost. See the glossary for worked examples.
The IRS standard mileage rate — widely used as a benchmark for total driving cost including fuel, depreciation, insurance, and maintenance — was 67¢ per mile for 2024. That is a broad average across vehicle types and ages. This calculator computes fuel cost only, which is typically 10 to 20 cents of that total depending on your car's efficiency and local gas prices.
Both scale the result linearly, but MPG is something you can influence. A 5 MPG improvement on a 25 MPG car (to 30 MPG) cuts cost per mile by about 17 percent. A 50-cent drop in gas price on a $3.50 gallon cuts it by about 14 percent. Gas price fluctuates daily and is outside your control; MPG is largely fixed by your car but you can recover a few percent through smoother acceleration, lower highway speed, and proper tire inflation. Over many miles, a more efficient car compounds the savings.
According to the Federal Highway Administration, the average American drives approximately 14,000 to 15,000 miles per year. Commuters in suburban or rural areas often exceed that; urban dwellers who use transit frequently drive less. The calculator defaults to 12,000 miles as a conservative round number — adjust it to match your own odometer readings for an accurate annual estimate.
Common mistakes
Cost-per-mile errors usually come from plugging in the wrong MPG for the type of driving being costed, or from forgetting that fuel is only one component of total per-mile cost.
Using highway MPG to cost a city commute, or vice versa
MPG differs substantially between driving types. EPA city and highway ratings can vary by 30–50% for the same vehicle. Using the highway figure to estimate a stop-and-go commute will significantly understate fuel cost per mile. Use the EPA city rating for urban commutes, the highway rating for highway-dominant trips, or your own observed fill-up data when it is available.
Treating fuel cost as total cost per mile
Fuel is typically 30–40% of total per-mile vehicle cost for average drivers. The remainder covers depreciation, insurance, maintenance, tires, registration, and financing. Using fuel cost alone to compare driving versus a rideshare or rental severely understates the true cost of ownership per mile — though it can validly estimate the marginal cost of an additional trip in a car you already own and insure.
Using MSRP instead of actual purchase price for depreciation in a combined cost model
If you are calculating a true all-in cost per mile that includes depreciation, the depreciation base should be what you actually paid, not the sticker price. A car purchased at $4,000 below MSRP depreciates from its actual purchase price, not the manufacturer's suggested retail price. Using MSRP inflates the depreciation component and overstates total per-mile cost.