{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"cat-age"},"result":{"entity_type":"calculator","id":"cat-age","calculator_id":"cat-age","canonical_url":"https://tttkmbb.com/everyday/cat-age","name":"Cat Age Calculator","title":"Cat Age in Human Years Calculator – 15 + 9 + 4 per Year Rule and Feline Life Stages","category":"everyday","category_name":"Everyday Life","tool_name":"convert_cat_age_to_human_years","featured_mcp_tool":false,"description":"Converts a cat's age to human-equivalent years with the veterinary convention used by International Cat Care and the AAHA/AAFP chart (first year 15, second year 9, then 4 per year) and assigns the International Cat Care life stage (kitten, junior, adult, mature, senior, super senior).","use_when":"You want a cat's age in human years or its life stage for feeding, vaccination or health-check planning.","do_not_use_when":"The animal is a dog (use dog-age, which adjusts for breed size) or you need calorie needs (use pet-calories).","inputs":[{"name":"cat_age_years","label":"Cat's age","type":"number","unit":"years","required":true,"min":0.1,"max":40,"description":"Age of the cat in years (e.g. 0.5 for six months).","example":5}],"outputs":[{"name":"human_years","label":"Human-equivalent age","type":"number","unit":"years","decimals":1,"description":"Human years by the 15 / 9 / 4-per-year convention (six months ≈ 10)."},{"name":"life_stage","label":"Life stage","type":"string","decimals":4,"description":"International Cat Care stage: kitten (0–6 months), junior (7 months–2 years), adult (3–6), mature (7–10), senior (11–14), super senior (15+)."},{"name":"next_stage","label":"Next stage","type":"string","decimals":4,"description":"The following life stage and the cat age at which it begins."}],"input_schema":{"type":"object","properties":{"cat_age_years":{"description":"Age of the cat in years (e.g. 0.5 for six months). Unit: years.","type":"number","minimum":0.1,"maximum":40,"examples":[5],"x-unit":"years"}},"additionalProperties":false,"required":["cat_age_years"]},"output_schema":{"type":"object","properties":{"human_years":{"description":"Human years by the 15 / 9 / 4-per-year convention (six months ≈ 10). Unit: years.","type":"number","x-unit":"years"},"life_stage":{"description":"International Cat Care stage: kitten (0–6 months), junior (7 months–2 years), adult (3–6), mature (7–10), senior (11–14), super senior (15+).","type":"string"},"next_stage":{"description":"The following life stage and the cat age at which it begins.","type":"string"}}},"formula":"age ≤ 0.5: 20·age; 0.5–1: 10 + 10·(age − 0.5); 1–2: 15 + 9·(age − 1); age > 2: 24 + 4·(age − 2)","method":"The convention approximates feline maturation: a 1-year-old cat is roughly a 15-year-old human and a 2-year-old about 24; after that each cat year adds about four human years. Individual cats vary with genetics, diet and indoor/outdoor life.","sources":[{"name":"International Cat Care – How to tell your cat's age in human years","url":"https://icatcare.org/advice/how-to-tell-your-cats-age-in-human-years/","type":"reference","retrieved_at":"2026-09-24"},{"name":"AAHA (2019) Canine and Feline Age Chart – physiological age in human years by size class","url":"https://www.aaha.org/wp-content/uploads/globalassets/02-guidelines/canine-life-stage-2019/canine_and_feline_age_chart_poster.pdf","type":"standard","retrieved_at":"2026-09-24"},{"name":"AVMA – Senior pets: how a pet's age compares with a human's","url":"https://www.avma.org/resources-tools/pet-owners/petcare/senior-pets","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"5-year-old cat","inputs":{"cat_age_years":5},"expected":{"human_years":36,"life_stage":"Adult","next_stage":"Mature from 7 years"},"url":"https://tttkmbb.com/api/v1/calculate/cat-age?cat_age_years=5"},{"name":"12-year-old cat","inputs":{"cat_age_years":12},"expected":{"human_years":64,"life_stage":"Senior","next_stage":"Super senior from 15 years"},"url":"https://tttkmbb.com/api/v1/calculate/cat-age?cat_age_years=12"}],"faq":[{"q":"When is a cat considered senior?","a":"International Cat Care uses 11 years (super senior from 15); the AAHA/AAFP guidelines start the senior stage at 10. Many vets recommend twice-yearly check-ups from about 10 years."},{"q":"Do indoor and outdoor cats age differently?","a":"The conversion is the same, but outdoor cats face more injury and disease, so their life expectancy is shorter on average."}],"tags":["cat age calculator","cat years to human years","how old is my cat","cat life stages","senior cat age"],"related":[{"calculator_id":"dog-age","reason":"Same conversion for dogs, adjusted for size."},{"calculator_id":"pet-calories","reason":"Daily calorie needs for cats by weight and life stage."}],"links":{"html":"https://tttkmbb.com/everyday/cat-age","markdown":"https://tttkmbb.com/everyday/cat-age.md","json":"https://tttkmbb.com/everyday/cat-age.json","api":"https://tttkmbb.com/api/v1/calculate/cat-age","schema":"https://tttkmbb.com/api/v1/calculators/cat-age","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T01:45:31Z"}