How does Digi-Key list the length on coiled modular cables?
We list the length of the cables when they are extended. To find retracted length that is typically listed on the datasheet.
For example we can look at part A2662R-07C-ND which we list as 7’ for the length.
and the datasheet has this chart 
You can view the full datasheet here.
Click here for some more coiled modular cable options to look at.