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Compare two dogs by age

Two dogs, side by side, in human-equivalent years. Useful for multi-dog households, rescue assessments, and "wait, who's actually older?" debates.

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Dog 1 Details

Dog 2 Details

Dog 1
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Dog 2
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Their stories side-by-side.

How comparison works

Each dog is converted to human-equivalent years using the AKC size-based method: the first year counts as ~15 human years, the second adds 9 (total ~24), and every year after that adds 4–7 depending on size. The comparison then surfaces three things:

  • The two human ages side by side, big and readable.
  • Each dog's current life stage, mapped to AAHA Canine Life Stage Guidelines.
  • A plain-English summary of the gap — including whether the dogs are in the same stage despite different calendar ages.

Common scenarios

Multi-dog household. You have a 4-year-old Labrador and an 8-year-old Yorkie. Are they "peers" in human terms? Yes, almost exactly — the Lab is around 39, the Yorkie around 48. Different stages still: the Yorkie just entered "mature", while the Lab is solidly adult.

Rescue assessment. Comparing a senior Chihuahua to a young Mastiff lets adopters see at a glance that they're in similar emotional/physiological territory despite calendar differences.

Family debate. The classic "your dog is older than mine!" can be settled with two seconds and a calculator.

Method: American Kennel Club size-based formula. See the main dog age calculator for full methodology, sources, and the Wang epigenetic-clock comparison.

Frequently asked questions

Why compare two dogs?

Owners of multiple dogs often want to know how their ages stack up — for example, whether a 10-year-old Chihuahua is actually "older" than a 7-year-old Labrador in human terms (yes, slightly — but not by as much as you might expect).

Why do same-age dogs land in different life stages?

Larger breeds age faster. A 7-year-old Great Dane is in late-senior territory, while a 7-year-old Yorkshire Terrier is still solidly adult. The size-based AKC formula captures this — the comparison view shows the gap visually with two side-by-side timelines.

Which method does this comparison use?

The AKC size-based method. It is the most widely cited practical formula and best matches lived veterinary experience for dogs across the full size range. See the main calculator for the Wang epigenetic-clock method alongside it.

Can I save dogs and re-compare later?

Yes — use the main dog age calculator, save each dog to your browser, and they'll be available for future comparisons. Saved dogs are stored only in your browser, never on our servers.

Are mixed breeds supported?

Yes. Leave the breed dropdown on "Use size only" and pick the closest size band. If you do not know the size, estimate from adult weight: small under 20 lb, medium 20–50 lb, large 50–90 lb, giant over 90 lb.

← Back to the main Dog Age Calculator