How to find out your dog's birthday – or choose one

Many adopted dogs arrive without a known birth date. You can usually narrow it down to a few months, and then simply pick a date that feels right.

1. Check the paperwork first

• Adoption or shelter records often list an estimated age or date of birth.
• Breeder or previous owner – if you have their contact, ask.
• Microchip registry – some registrations include a birth date.
• Vaccination card – the date of the first puppy vaccines (often around 6–8 weeks old) lets you count back.

2. Ask your vet to estimate

Vets estimate age from teeth, eyes, coat, joints and overall body condition. It's an educated guess, more precise for young dogs than older ones.

3. What teeth can tell you (roughly)

• Under ~8 weeks: puppy (milk) teeth coming through.
• ~3–7 months: adult teeth replacing puppy teeth.
• Around 1 year: all adult teeth, clean and white.
• Older: yellowing, tartar and wear increase with age, but diet and dental care change this a lot – so it's only a rough guide for adult dogs.

4. Other clues

• Size compared to the expected adult size for the breed or mix.
• Grey hair around the muzzle (which can start early in some dogs).
• Cloudy eyes, stiffness and lower energy in senior dogs.
• A DNA breed test won't give an exact age, but helps predict adult size and growth.

5. Choosing a birthday

Once you know the approximate month, pick a date. Popular choices:

• The estimated date counted back from the vet's age.
• Your adoption day – celebrate it as their Gotcha Day.
• A meaningful date – a holiday, the first day of a season, or your own birthday so you share a cake day.
• January 1st – some shelters use it for dogs of unknown age, which makes counting years easy.

The exact date matters far less than having a day to celebrate them. When you've chosen it, set a free reminder so you get an email a week before, and plan a small party.

Celebrating soon? Make a birthday card with your dog's photo – free preview.

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