What is the typical number of years that house cats live?

I have a cat that is about 15 years old. I am wondering how old they usually live to be.

Well we have a cat right now who is 13 years old. But to better answer that question, a friend of mine has a cat that is actually 27 years old now. I know, it shocked me too, the cat is a year older than her! Their cats are all kept on a dry food diet though, and are also all inside pets, that could be the reason. All of the cats they have (except for two) are over 17 years. It all depends on diet and care. =P

around 19 years with good vet care and a lot of tenderloving from owner.

Mine lived to 18 and 19, which seems to be about the top age, except in rare cases.I've noticed a trend that at about 16 years of age, they start declining faster and start to seem old. Their claws seem to stop retracting, so you need to keep them trimmed and help them more with grooming.

Indoor house cats can live over 20 years, but average closer to 16 years old. The maximum is over 30 years. Outdoor and in/out cats have reduced lifespans due to extra exposure to risks and diseases. Excess weight also severly reducing the expected lifespan of a cat due to the strain it puts on their bodies and joints. If your 15-year-old is slim and in good health and has regular vet visits, she can live another 5 or 10 years. Older cats need their teeth cleaned, might need additional grooming because they are not as flexable as when they were younger, and she should have yearly blood work done to ensure her internal organs are functioning well (kidneys, thyroid, livers, etc).