Fuel cost = (miles ÷ MPG) × price per gallon. Cost per mile is just the pump price divided by your MPG — at $3.89 and 6.5 MPG, about 59.8¢ every mile, loaded or empty. Put your own numbers in below, including the deadhead, and add the load pay to see what fuel leaves behind.

Truck Fuel & Trip Cost Calculator

Price the diesel on a run before you take it: miles, MPG, and pump price give you gallons burned, total fuel cost, and cost per mile. Add the load pay to see what fuel leaves on the table.

Gear that pays for itself on the road

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Why the trip that looked good lost money

Diesel is the biggest single variable cost in trucking, and it is the one that turns a load that looked fine on the board into a week you would rather forget. The arithmetic is not hard. What catches people out is which miles they count and which price they use.

Start with every mile the truck will actually turn. That means the loaded miles plus the deadhead to get to the pickup and away from the delivery. Empty miles burn nearly as much fuel as loaded ones and pay nothing, so leaving them out of the calculation does not make them disappear — it just moves the surprise to the end of the month. A 500-mile load with 50 miles of deadhead is a 550-mile run, and that is the number your fuel spend is built on.

Then use an honest MPG. Not the brochure figure, not your best empty downhill tank — your recent loaded average. The difference matters more than most drivers expect: at $3.89 a gallon, the gap between 5.5 and 6.5 MPG is about eleven cents a mile. Over 10,000 miles that is roughly $1,100, which is a truck payment for a lot of operators.

How this calculator works

The math is deliberately transparent so you can check it on a napkin. Total miles are the loaded miles (doubled if you mark it a round trip) plus your deadhead, which is never doubled because you enter it as a total. Gallons are total miles divided by your MPG. Fuel cost is those gallons multiplied by the price per gallon you entered. Fuel cost per mile is the fuel cost divided by the total miles, which always works out to the pump price divided by your MPG — the reason cost per mile does not change with trip length.

If you enter the load pay, it also shows what is left after diesel, fuel as a share of the pay, and the revenue per mile the run is really offering. Money figures are rounded to the cent and per-mile figures to a tenth of a cent, because at 10,000 miles a month a tenth of a cent is ten dollars.

What it does not model: idle time, terrain, weather, load weight, reefer fuel, or APU burn. Those all move real consumption, which is why you should use your own observed MPG rather than an ideal one. It also applies no fuel-card discount — enter your discounted price if you want the net number. This is a planning estimate, not an accounting record.

Worked examples

Truck fuel cost questions, answered

How do I calculate fuel cost for a trip?
Divide the total miles by your truck's average MPG to get the gallons you will burn, then multiply those gallons by the price per gallon. A 550-mile run at 6.5 MPG burns about 84.6 gallons; at $3.89 a gallon that is roughly $329 in diesel. The shortcut for cost per mile is even simpler: divide the pump price by your MPG. At $3.89 and 6.5 MPG every mile costs about 59.8 cents in fuel, no matter how long the run is.
Should I include deadhead miles?
Always. Empty miles burn diesel at close to the same rate as loaded miles but earn nothing, and they are the most common reason a load that looked profitable was not. Enter your deadhead as a total for the run — the calculator adds it to the loaded miles before working out gallons, so the cost per mile you see is the real cost of the whole trip, not just the paid portion.
What MPG should I use?
Use your own recent average, not the number the truck was sold on. Most modern sleeper tractors running loaded average somewhere between 5.5 and 7.5 MPG, and the spread inside that range is worth real money: at $3.89 diesel, moving from 5.5 to 6.5 MPG saves about 11 cents a mile, or roughly $1,100 over 10,000 miles. Terrain, weather, idle time, speed, and load weight all move it, so if you run mountains in winter, do not plan with your best flatland summer number.
Does this account for fuel-card discounts?
Not automatically. The calculator uses whatever price per gallon you type in, so if you pull a discounted price at the pump through a fuel card or a network program, enter that discounted figure and the result reflects your true net cost. If you enter the posted retail price, treat the answer as your worst case.
How much of a load's pay should fuel be?
There is no single right answer, but it is the ratio experienced operators watch first. Enter the load pay and the calculator shows fuel as a percentage of revenue. Fuel is only one line in your cost structure — your truck payment, insurance, maintenance, and tolls still have to come out of what is left — so a run where fuel alone takes a large share of the pay rarely survives the rest of the math. Use the cost per mile calculator to see the full picture.

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