Idle cost calculator: what a night of idling costs you

Idling is fuel you burn without moving a mile. An hour here and there feels free, but a truck that idles through every rest break and every night can spend thousands of dollars a year doing it. This idle cost calculator turns your idle hours, your engine's burn rate and your diesel price into dollars per hour, per day and per year.

Semi truck idling fuel consumption

The U.S. Department of Energy puts semi truck idle fuel consumption at about 0.8 gallons per hour, with a typical range of 0.6 to 1.5 gallons per hour. The same fact sheet estimates a long-haul truck idles about 1800 hours a year, burning around 1,500 gallons of diesel. Your truck can sit well above or below that: a bigger engine, a high idle setting, or running the air conditioning hard in summer all push the burn up.

POSTED: DOE Vehicle Technologies Office, Long-Haul Truck Idling Burns Up Profits (2015) · checked Oct 2026

Diesel prices change the cost more than anything. The default here is the EIA U.S. average of $6.199 a gallon for the week of October 5, 2026; you can fill in any EIA region or type your own price.

How it is calculated

1. Gallons a day: idle hours a day times gallons per idle hour.
2. Cost a day: gallons a day times your diesel price.
3. Hours a year: idle hours a day times the days you idle like that.
4. Cost a year: hours a year times burn rate times price, and the same divided by 12 for a month.
5. Per idle hour: burn rate times price, the number to remember at the fuel island.

What a good result and a bad result look like

A good result is idling you chose: a few hours on a brutal night, with most rest periods covered by a heater, a battery system or an APU. A bad result is idling out of habit, every break, all year, which can cost more than your truck insurance. Fuel is only part of it; idle hours also add engine wear, oil changes and DPF loading.

The alternatives burn far less. The same DOE fact sheet lists a diesel-fired bunk heater at 0.04 to 0.08 gallons per hour (diesel-fired heater) and a diesel APU at 0.2 to 0.5 gallons per hour (diesel APU), against 0.6 to 1.5 gallons per hour for the main engine. Whether one is worth buying depends on your idle hours; the APU payback calculator works that out.

Where you park decides how much choice you have. Some lots offer plug-in power, and paid parking may be cheaper than a night of idling; truck parking prices compares the options. Short idle stops add up too, which is one reason drivers use a weigh station bypass app where their state and program allow. To see what moving miles cost in fuel, use the trip fuel cost calculator.

Fewer wasted hours, fewer wasted gallons

Long waits at shippers and a night in the wrong place both mean idle time. Planning around that is part of a dispatcher's job: our dispatchers plan loads around your hours and home time and aim each day to end at a stop that suits how you rest. If you are weighing the cost of that help, the dispatcher fee calculator puts it in dollars. You confirm every load and get the rate con yourself. See how it works for owner operators, or apply in about two minutes.