Dog Years to Human Years — Complete Age Table by Size

1 dog year does not equal 7 human years. The accurate conversion depends on your dog’s size. Small breeds age more slowly than giant breeds after year two. Use this complete table to find your dog’s human-age equivalent instantly — or use the dog age calculator for a precise result by birthday.

Source: AVMA size-adjusted dog age tables · Last updated: June 2026 · Use the full calculator →

Complete Dog Age to Human Years Table — All Sizes (Age 1–20)

This table covers every dog age from 1 to 20 years across all four size categories: Small (under 10 kg), Medium (10–25 kg), Large (25–45 kg), and Giant (45+ kg). Find your dog’s age in the left column and read across to their size.

Dog AgeSmall
under 10 kg
Medium
10–25 kg
Large
25–45 kg
Giant
45+ kg
Life Stage
1 year15151512Puppy
2 years24242422Adolescent
3 years28282831Adult
4 years32323238Adult
5 years36363645Adult
6 years40424549Adult / Mature Adult (Giant)
7 years44475056Mature Adult / Senior (Large+)
8 years48515564Mature Adult / Senior (Large+)
9 years52566171Senior
10 years56606679Senior
11 years60657286Senior
12 years64697793Senior / Geriatric (Giant)
13 years687482100Senior / Geriatric
14 years727888107Geriatric
15 years768393114Geriatric
16 years808799121Geriatric
17 years8492104Geriatric
18 years8896109Geriatric
19 years92101115Geriatric
20 years96105120Geriatric

— Giant breeds rarely exceed 15 years. Source: AVMA size-adjusted dog age guidelines.

How to Read This Table

For a precise result using your dog’s exact birthday and a choice of Simple, Advanced, or Scientific mode — use the Dog Age Calculator.

Quick Answers by Age

How old is a 1-year-old dog in human years?

A 1-year-old dog is approximately 15 human years regardless of size. Dogs develop extremely rapidly in their first year — reaching sexual maturity and adult teeth well before their first birthday.

How old is a 2-year-old dog in human years?

A 2-year-old dog is approximately 24 human years for small, medium, and large breeds, and approximately 22 human years for giant breeds. This is the Adolescent stage transitioning into early Adult.

How old is a 3-year-old dog in human years?

A 3-year-old small, medium, or large dog is approximately 28 human years. A 3-year-old giant breed is approximately 31 human years. Both are solidly in the Adult stage.

How old is a 5-year-old dog in human years?

A 5-year-old small or medium dog is approximately 36 human years — prime adult stage. A 5-year-old large dog is also approximately 36 human years. A 5-year-old giant breed is approximately 45 human years, entering early Mature Adult.

How old is a 7-year-old dog in human years?

A 7-year-old small dog is approximately 44 human years. A medium dog is approximately 47 human years. A large dog is approximately 50 human years. A giant breed is approximately 56 human years and is already Senior.

How old is a 10-year-old dog in human years?

A 10-year-old small dog is approximately 56 human years. A medium dog is approximately 60 human years. A large dog is approximately 66 human years. A giant breed is approximately 79 human years — firmly Geriatric.

How old is a 13-year-old dog in human years?

A 13-year-old small dog is approximately 68 human years. A medium dog is approximately 74 human years. A large dog is approximately 82 human years. A giant breed is approximately 100 human years — deep Geriatric stage.

How old is a 15-year-old dog in human years?

A 15-year-old small dog is approximately 76 human years. A medium dog is approximately 83 human years. A large dog is approximately 93 human years. Giant breeds rarely reach 15 years.

Use the Full Dog Age Calculator

This table gives you a quick lookup. For a precise result using your dog’s exact birthday, size, and choice of calculation mode (Simple, Advanced, or Scientific epigenetic formula), use our full Dog Age Calculator. It also covers cats using AAFP guidelines.

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