You really shouldn't "dock" or cut a dog's tail off. But as far as natural length goes, it depends on the breeds.
how long do you leave a doberman tail
When it is a DOG.
If you adopt a six-week old Boxer puppy with an undocked tail, there is no need to take it to the vet, it is to late to have the tail docked.
A Shorkie adults tail only gets cut when it is frightened. A puppy does not.
More info has to be given even for a guess.
At a similar age to when you had your coccyx severed.
for looks
3-4 mm tail
Yes, mine was born with a short tail
Three to four months. That's how long we leave it on our Arabians, other wise their tails can start to rot. (left one in for 6 months, took it off and half the tail was gone)
When they aren't looking
Tail docking in puppies is typically done when they are between 2-5 days old, as this is the window where the procedure is least stressful and painful for the puppy. It is usually performed by a veterinarian using surgical techniques to ensure the safety and health of the puppy. It is important to follow breed standards and regulations regarding tail docking.