Deadhead
The empty miles you drive to get to a pickup, with no freight on the trailer and no one paying for them.
Deadhead is the miles you run empty. Most often it is the drive from where you dropped your last load to where you pick up the next one, with nothing on the trailer. Nobody pays you for those miles, but they still burn fuel, wear the truck, and eat your hours.
That is why deadhead matters when you size up a load. A load that pays well on loaded miles can turn thin once you count the empty miles it took to get to it. The honest number is your all-in rate: the pay divided by loaded plus deadhead miles, not loaded miles alone.
You cannot get deadhead to zero, but you can keep it low by booking loads that start near where your last one ends. The rate per mile calculator counts deadhead for you so you can see what a load really pays.
Related: rate per mile, fuel surcharge, rate confirmation.