liminfoDog Age Calculator
Free web tool: Dog Age Calculator
Breed preset (auto-selects size)
Breed Size
About Dog Age Calculator
The Dog Age Calculator converts your dog's chronological age into the equivalent human age using a logarithmic formula derived from recent veterinary epigenetic research. Unlike the outdated "multiply by 7" rule, this tool accounts for breed size — small (<10 kg), medium (10–25 kg), and large (>25 kg) dogs each have distinct formulas: Small: 12.5 × ln(age) + 28.8 | Medium: 14 × ln(age) + 31 | Large: 16 × ln(age) + 31.
Popular Korean breed presets — Maltese, Toy Poodle, Pomeranian, Shiba Inu, Jindo, Golden Retriever, Labrador — automatically set the correct size category so you never have to guess. A life stage progress bar (Puppy → Junior → Adult → Senior → Geriatric) gives instant visual feedback on where your dog sits in its lifespan.
After calculating, use the built-in SNS share card generator to produce a 600×340 PNG image featuring your dog's name, breed size, dog age, human-equivalent age, and life stage. Copy to clipboard for direct paste into KakaoTalk, Instagram Stories, and other platforms — or download as a PNG file.
Key Features
- Logarithmic formula (12.5–16 × ln(age) + constant) matched to Small / Medium / Large breed research
- Seven popular Korean breed presets that auto-select the correct size class
- Life stage progress bar: Puppy → Junior → Adult → Senior → Geriatric with color coding
- SNS share card: 600×340 PNG with dog name, breed, human age, life stage — copy or download
- Optional dog name field personalized on share card and download filename
- Supports fractional ages (step 0.5) for precise puppy calculations
- 100% client-side — no data sent to server, works offline after page load
- Dark mode support and fully responsive for mobile and desktop
Frequently Asked Questions
Why is the logarithmic formula better than multiplying by 7?
The logarithmic formula (based on epigenetic clock research) reflects the biological reality that dogs age very rapidly in the first 1–2 years and then slow down. Multiplying by 7 produces a linear relationship that is demonstrably wrong — a 1-year-old dog is more like a 30-year-old human, not a 7-year-old.
What is the formula for small dogs (<10 kg)?
Human age = 12.5 × ln(dog age) + 28.8. For example, a 3-year-old Maltese: 12.5 × ln(3) + 28.8 ≈ 12.5 × 1.099 + 28.8 ≈ 42.5 human years — solidly in the Adult stage.
What is the formula for large dogs (>25 kg)?
Human age = 16 × ln(dog age) + 31. A 7-year-old Golden Retriever: 16 × ln(7) + 31 ≈ 16 × 1.946 + 31 ≈ 62.1 human years — in the Senior stage. Large breeds cross into Senior territory years earlier than small breeds.
Which life stage needs the most veterinary attention?
Senior (55–74 human equivalent) and Geriatric (75+) dogs benefit from twice-yearly vet checkups, joint supplements, dental cleanings, and bloodwork panels. For large breeds this typically begins around 7 dog years; for small breeds around 11–12 years.
How do the breed presets work?
Clicking a breed name (e.g. 진돗개 / Jindo) automatically selects the matching size category — Jindo selects Medium. You can then fine-tune the size manually if your specific dog is atypically large or small for its breed.
How does the SNS share card work?
After entering a dog name and age, click "Copy Image" or "Download Image". The tool draws a 600×340 PNG on an invisible canvas with a dark gradient background, accent color, dog name, breed size, computed human age, and life stage badge — then delivers it to your clipboard or as a file download.
Can I enter ages under 1 year?
The logarithmic formula uses ln(age), which is undefined for age = 0. Use the minimum step of 0.5 years (6 months) as the smallest valid input. A 6-month-old puppy of any size is in the Puppy stage with a very low human-equivalent age.
Why are the Korean breeds Maltese, Jindo, and Shiba Inu included?
These are among the most popular breeds owned in South Korea. The presets help Korean users quickly identify the correct size class without having to research their dog's weight range independently.