Puppies get 28 baby teeth at 3–8 weeks and 42 adult teeth between about 3½ and 7 months. A full set of sharp baby teeth usually means 6–14 weeks; all-white adult teeth usually mean under 1–2 years.
How to tell a puppy's age by its teeth
Teeth are the single best clue to a young dog's age. Shelters, rescue groups and even the USDA use tooth eruption to age puppies because baby and adult teeth arrive on a reliable schedule. For puppies under 7 months, teeth can usually pin the age down to within a few weeks.
Dogs get two sets of teeth. Puppies have 28 deciduous (baby) teeth, which start to erupt at about 3 weeks and are all in by 6–8 weeks. These are replaced by 42 permanent adult teeth between about 3½ and 7 months.
Puppy teeth age chart
| Approx. age | What you'll see | Teeth |
|---|---|---|
| 0–2 weeks | No teeth yet | 0 |
| 3–5 weeks | Tiny baby canines & incisors | Some of 28 |
| 5–8 weeks | Baby premolars coming in | Up to 28 |
| 8–14 weeks | Full set of sharp baby teeth | 28 baby teeth |
| 3½–5 months | Adult front teeth coming in | Mixed |
| 5–7 months | Adult canines & molars arriving | Mixed → 42 |
| 7–12 months | All adult teeth, bright white | 42 adult teeth |
| 1–2 years | White with slight wear | 42 |
| 3–5 years | Some yellowing & tartar | 42 |
| 5–10 years | Heavy tartar, worn teeth | Often 42 |
| 10+ years | Very worn, loose or missing teeth | Some missing |
Baby tooth timeline
- Baby canines and incisors: about 3–5 weeks
- Baby premolars: about 4–8 weeks (all 28 baby teeth by 6–8 weeks)
Adult tooth timeline
- Adult incisors: about 3–5 months
- Adult canines: about 4–6 months
- Adult premolars: about 4–6 months
- Adult molars: about 4–7 months — all 42 adult teeth by about 7 months
Estimating an adult dog's age from teeth
After all adult teeth are in, vets look at wear and tartar. Clean, white teeth usually mean 1–2 years; yellowing and tartar on the back teeth suggest 3–5 years; heavy tartar and worn tips suggest 5–10 years; and loose or missing teeth are common in dogs over 10. Diet, chewing habits and dental care change this a lot — a dog with regular cleanings can look years younger — so combine teeth with other signs like a greying muzzle, cloudy eyes and energy level.
Once you know the approximate age, use the puppy age calculator or dog age by breed calculator to convert it into human years.
Aging a horse instead? Horses are aged by their incisors, cups and Galvayne's groove — try the horse age by teeth estimator.
Frequently asked questions
How can you tell a puppy's age by its teeth?
Look at which teeth are present. No teeth = under 3 weeks; tiny baby canines and incisors = 3–5 weeks; a full set of 28 sharp baby teeth = 6–14 weeks; adult front teeth coming in = 3½–5 months; all 42 white adult teeth = about 7–12 months.
How many teeth does a puppy have?
Puppies have 28 baby (deciduous) teeth. Adult dogs have 42 permanent teeth.
When do puppies lose their baby teeth?
Baby teeth start falling out at about 3½–4 months as adult incisors come in. Most puppies have all their adult teeth by 6–7 months.
Can you determine a dog's age by its teeth?
Yes for puppies — within a few weeks. For adult dogs teeth give a rough range (for example 3–5 years) because wear depends on diet, chewing and dental care.
What age do puppies get adult canine teeth?
Adult canines usually erupt at about 4–6 months. If a baby canine is still next to the adult one after about 6–7 months, ask your vet — it may need removal.
How old is a dog with tartar on its teeth?
Moderate yellowing and tartar on the back teeth are typical from about 3 to 5 years; heavy tartar is common after 5, though dogs with poor dental care can build tartar earlier.
This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.