How are package tracking numbers for FedEx and UPS assigned?

There are patterns like how numbers increase by 7 each time a new tracking number is assigned unless the new number does not increase the second digit.





Example:


one number is 013840222514114 at fedex


the next valid number is 013840222514121





but it skips 013840222514128


and goes to 013840222514138





My question is: what are the algorithms of assigning these numbers?How are package tracking numbers for FedEx and UPS assigned?
You pretty much figured it out. Not sure about UPS (see below), but FedEx Ground tracking #s like your examples are 15 digits long, whereas current Express #s are 12 digits long. UPS has much higher volume/market share than FedEx so they have to use letters in their #s.





It's kinda like the transaction code whenever you buy something and get your receipt. The # represents how many burgers have been sold so far (trillions!). If you really figure out the actual algorithm (if one indeed exists) for assigning such #s, then you've got something!How are package tracking numbers for FedEx and UPS assigned?
HAHAH...thats interesting....you know fedex has and arrow in the letters