PuppyweeksPuppy weeks 13–16
Puppy weeks 13–16: Teething & Boundary Testing
Weeks 13–16 bring adult teeth, relentless chewing, and boundary-testing as confidence grows. Fast growth can look briefly out of proportion — big paws, gangly legs — which is normal. Redirect biting to legal chews rather than punishing it, and start protecting still-forming joints from high-impact activity.
When does this happen?
| All breed sizes | Weeks 13–16 |
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Not sure this is your puppy’s exact stage? Check the Puppy Stage Finder. Want a clear plan for the biting and chewing phase? See the full training timeline.
Common questions
Why is my puppy biting so much at 4 months?
Adult teeth are pushing through, so chewing and mouthing spike around weeks 13–16. Redirect to chew toys rather than punishing the biting, which only raises arousal. Biting that regularly breaks skin or comes with stiffening or growling is worth a certified trainer.
When should I switch to a large-breed puppy food?
It’s generally worth discussing once a puppy is projected to reach roughly 50–70lb or more as an adult, since these formulas control calcium and calorie density. Ask your vet, and skip calcium supplements — young puppies can’t self-regulate excess dietary calcium the way adults can.
Grounded in established canine behavioural science — see our sources.