New Puppy Checklist
Enter your puppy's age and size to get a personalized timeline — vaccines, spay/neuter timing, food transitions, and other milestones, adjusted for how fast your size of dog grows. Small and giant breeds hit these milestones at very different ages.
General guidance based on AAHA vaccination guidelines and common veterinary timing recommendations — not a substitute for your vet's specific plan. Spay/neuter timing especially varies by individual dog; talk to your vet.
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Crate, bed, starter food, and training supplies — sized for a new puppy's first few months at home.
Browse new puppy essentials on Amazon(affiliate link)Why size changes the timeline
Small breeds finish growing and reach adult food by 9-10 months. Giant breeds can still be growing at 18-24 months, and many vets now recommend waiting longer before spay/neuter surgery in large and giant breeds to let growth plates close first. A single generic "puppy checklist" that ignores size gets this wrong for most dogs — see our puppy growth stages guide for the full science behind this.
How accurate is it?
The vaccine timing follows current AAHA guidelines closely and is reliable as a general reference; the spay/neuter windows are broader and reflect an area of active, evolving veterinary discussion rather than a single fixed rule — some vets weigh individual factors (specific breed, behavior, shelter/rescue policy) differently within those ranges. Growth and food-switch timing are estimates based on typical size-category curves, so an individual puppy tracking notably ahead or behind their size category may hit those milestones a few weeks earlier or later than shown.
Data sources
Vaccine timing and the leptospirosis core-vaccine recommendation follow the 2022 AAHA Canine Vaccination Guidelines (updated 2024). Growth and food-switch timing use the same size-based growth-curve research as our Puppy Weight Predictor tool (linked below). Spay/neuter timing reflects commonly cited veterinary guidance on waiting for growth plate closure in large and giant breeds; always confirm the specific plan with your own vet.
Frequently asked questions
Why does spay/neuter timing depend so much on size?
Because large and giant breeds take much longer to finish growing, and many vets now recommend waiting for growth plates to close first. Spaying/neutering before growth is complete has been linked to a higher risk of certain joint conditions in some large breeds, which is why the window stretches out to 12-18 months for large breeds and 15-21 months for giant breeds, versus around 6 months for small and medium breeds. This is a genuine, evolving area of veterinary guidance — your vet's specific recommendation for your individual dog should take priority over this general timeline.
My puppy is already past some of these milestones — is that a problem?
No — generate the checklist with their current age and anything already marked "done by now" just confirms what should already have happened. If a core milestone (like the initial vaccine series) was genuinely missed rather than just already completed, that's worth a call to your vet, but the checklist itself isn't diagnosing anything; it's just a timeline reference.
Is leptospirosis vaccination really necessary for every dog?
AAHA's 2022 Canine Vaccination Guidelines (updated 2024) now list leptospirosis as a core vaccine recommended for all dogs, not just ones with obvious exposure risk like frequent hiking or standing water — this was a change from older guidance that treated it as optional based on lifestyle. Talk to your vet if you have specific concerns, but the current veterinary consensus is that it belongs in the core series for essentially every dog.
Why does the timeline stretch out so much for giant breeds?
Because giant breeds are still developing well past the age most people consider a dog "grown" — many don't reach full adult weight until 18-24 months, and their spay/neuter window is pushed later for the same growth-plate reasons. If you have a giant-breed puppy, expect this checklist to run noticeably longer than it would for a friend's medium-breed puppy of the same age.
What if my vet recommends something different from this checklist?
Follow your vet — this checklist reflects general AAHA guidelines and common timing, but your vet knows your specific puppy's health history, local disease risk, and any individual factors that should change the plan. This is a reference for understanding the general shape of the first two years, not a substitute for your vet's actual recommendations.