Dog Years to Human Years Chart — All Sizes (Printable Table)

Dog Age Conversion Table (All Size Classes)

Values follow the modern veterinary guideline: 15 human years for year one, 9 for year two, then 4 (small), 4.5 (medium), 5 (large), or 6 (giant) human years per dog year. For an exact figure including months, use the dog age calculator.

Dog's age	Small (<20 lb)	Medium (20–50 lb)	Large (50–90 lb)	Giant (>90 lb)
1	15	15	15	15
2	24	24	24	24
3	28	28.5	29	30
4	32	33	34	36
5	36	37.5	39	42
6	40	42	44	48
7	44	46.5	49	54
8	48	51	54	60
9	52	55.5	59	66
10	56	60	64	72
11	60	64.5	69	78
12	64	69	74	84
13	68	73.5	79	90
14	72	78	84	96
15	76	82.5	89	102
16	80	87	94	108

Cat Years to Human Years Chart

Cats follow a single curve regardless of breed. Get an exact figure with the cat age calculator.

Cat's age	Human years	Cat's age	Human years
1	15	9	52
2	24	10	56
3	28	12	64
4	32	14	72
5	36	16	80
6	40	18	88
7	44	20	96
8	48	22	104

Life Stage Reference

Size changes when each stage begins. These are the ages many veterinarians use for wellness planning.

Size class	Puppy	Adult	Senior from
Small	0–1 yr	1–8.5 yrs	~8.5 yrs
Medium	0–1 yr	1–8 yrs	~8 yrs
Large	0–1 yr	1–7 yrs	~7 yrs
Giant	0–1 yr	1–6 yrs	~6 yrs

Read the full explanation of the science in our guide: How Old Is My Dog in Human Years?