Semi truck fill-up cost calculator

Know the bill before you pull up to the pump

Fuel is the biggest running cost for most trucks, and a fill-up on a semi is one of the largest single purchases a driver makes in a week. Knowing the number before you pull in helps with more than the budget. It tells you whether the fuel card limit will cover it, whether to fill all the way or buy enough to reach a cheaper stop, and how much cash to hold back until the next load pays.

This semi truck fill-up cost calculator works from the gauge. Pick the level you see, put in the price at the pump, and it shows the gallons needed and the cost. It also shows the range on full tanks, so you can plan where the next stop needs to be.

How the fill-up cost is calculated

Total capacity is the number of tanks times the gallons each holds. The gallons to fill are that capacity times the part that's empty. If the gauge reads a quarter, three quarters of the capacity is empty. The cost is those gallons times the price per gallon. The range is full capacity times your miles per gallon.

• EXAMPLE

  EXAMPLE FILL

  Two 120-gallon tanks at a quarter

  Capacity is 240 gallons. At a quarter full, 180 gallons are needed. At an EXAMPLE price of $4.00 a gallon, the fill costs $720. From empty, it would be $960. At 6.5 miles per gallon, full tanks carry the truck about 1,560 miles, before the reserve most drivers keep.

Fuel gauges on trucks aren't precise, especially near the top and bottom, and tanks on uneven ground read differently. Use the result to plan, and expect the pump to differ by a few gallons.

Semi truck fuel tank capacity

Most tractors carry two side-mounted fuel tanks, one on each side, and some carry one. Tank sizes vary by make, model and how the truck was ordered. Many common tanks hold somewhere between about 100 and 150 gallons each, but some are smaller and some fleets spec larger ones for range. The only number that matters is yours, so check the label on the tank, the build sheet or the spec sheet for your VIN.

If you don't have the spec sheet, our semi truck VIN decoder pulls the make, model, year and engine from NHTSA's database. It won't list tank size, but it's a fast way to find the right build information. Remember that usable capacity is a little less than the rated size, because tanks are never filled to the very top and the pickup tube can't draw the last bit.

Fill all the way, or buy enough to reach a cheaper stop?

Diesel prices vary from state to state, partly because of different fuel taxes, and from one truck stop to the next on the same highway. Full tanks give you range and flexibility. A partial fill can make sense when a cheaper stop is within range on your route, or when cash is tight until a load pays.

The trade-off is simple: weight and money now against price and flexibility later. Diesel weighs about 7 pounds a gallon, so a full fill on a heavy load can matter for your legal weight. And a planned cheap stop that turns into a closed lot or a long line costs more than the few cents you saved.

Reading your result

• +The cost is more than your fuel card allows. Split the fill or arrange the limit before you're at the pump.
• +The range is shorter than the next stretch. Plan the stop now, with a backup, so you're not choosing a stop on a low tank.
• +The bill is a big share of the load's pay. Check the load's rate against your cost per mile. The trucking cost per mile calculator shows how much of every mile is fuel.

For a whole trip rather than one fill, the trip fuel cost calculator works out the fuel cost from miles, mpg and price.

Fuel and the loads you book

Every load you take spends fuel on its loaded miles and on the empty miles to the pickup. Our dispatchers count both before they counter, so the rate covers the fuel you'll actually burn. You keep the final say on every load, and the rate confirmation comes to you directly. See how we work with owner-operators.

Fuel prices and the balance of trucks and loads both move rates. Our guides on full truckload rates and the load-to-truck ratio explain how.