See how much idling really costs your fleet in fuel and engine wear each year, and what cutting it would save.
What idling costs
An idling Class 8 engine typically burns in the region of 0.8 gallons of diesel per hour, and many trucks idle for hours every day across overnight rests, dock waits and warm-ups. The calculator multiplies your daily idle hours by fuel burn and the diesel price, adds an allowance for the engine wear that idle hours put on oil, injectors and aftertreatment systems without adding a single revenue mile, and scales it across the fleet and year. At 2026 record diesel prices, two idle hours a day can quietly cost several thousand dollars per truck annually.
Where the hours come from
The Department of Energy's idling research identifies overnight hotel-load idling (heating, cooling and appliances during rest periods) and workday idling (queues, docks, warm-ups and habit) as the main drivers, with long-haul trucks historically among the biggest idlers. Telematics idle reports are the fastest way to find your real number: most fleets are surprised by it, which is why the default reduction target here is set at an achievable 50 percent rather than zero.
Cutting it
Proven measures include auxiliary power units and battery HVAC for overnight loads, automatic engine shutdown timers, driver scorecards built on telematics idle data, and simply planning warm-ups out of the routine. Many states also enforce idle time limits with fines. Use the reduction slider to price your target, then weigh it against the cost of APUs or the telematics platform that would get you there.
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