After doing a spot of reading about this I have come to suspect that it is either not very well researched, or i have just been lucky. It concerns, as the title suggests, cats that are kept indoors vs cats that have their own means of entry and exit and are free to roam the local area. Sources online suggest that the life expectancy of an indoor cat is about 17. And these same sources say that the life expectancy of an outdoor cat is between 2-5 years: https://pets.webmd.com/cats/features/should-you-have-an-indoor-cat-or-an-outdoor-cat#1 In my lifetime i have had 6 cats. From pretty much kittenhood all the way to the end of their life. And we have always let them be free to roam the local area. Personally i think its a bit cruel to keep them indoors. I know that they are more at risk outdoors - from other cats and possibly even local wildlife or other pets (dogs). But it gives them license to go out and hunt and do cat things for a while. And i really dont like litter trays. And neither do my cats - much preferring instead to go outside (if we leave a litter tray out when the option to go outside exists then they will all studiously avoid the litter tray and go outside leaving the litter and tray redundant). So of my 6 cats - their names, ages and (if applicable) cause of death are as follows: Charlotte - 15 - Kidney failure (euthanised) Sheba - 16 - Kidney failure (euthanised) Solomon - 18 - Feline dementia (euthanised) Sylvie - 19 - Kidney failure (euthanised) Harpo - 6 - Alive and kicking Groucho - 6 - Alive and kicking Obviously where you live plays a role. Like on a busy street or in a city will presumably introduce more hazards to your cats health. But 2-5 years seems awfully low to me. Which leads me to believe the internet is lying to me. Thoughts?