I have "zero tolerance" on biting as well. I don't like it and it hurts and I let the puppy know this.
They need to learn bite inhibition, which is something they learn with their litter mates. They learn the strength of their bite by the reaction of their brothers and sisters.
Initially with a very young pup, I would allow a few bites and then squeek and remove myself from the puppy and ignore for a short time. This teaches them that if they bite, they don't get to play.
As the pup gets older I don't tolerate any biting at all, however, they are provided with toys to use and this can also be a good diversion from your bodily parts!
If they are having a mad five minutes, running around and snapping at things, they would be placed in another room to settle down. Puppies are social and they like the company and interaction, if they are deprived of this, the lesson seems to sink in quicker.