Cats are polyphasic sleepers, commonly totaling twelve to sixteen hours daily, more for kittens and seniors, the normal setup of an energy-conserving hunter.
Most feline sleep is light dozing with a modest deep-sleep share, so small sounds wake them and long totals actually represent fragmented rest.
The warning is not duration but sudden change: unrousable lethargy, poor waking energy, or a formerly calm cat that cannot settle.
Daytime hunting play and foraging improve sleep structure and calmer nights; persistent sleep changes with appetite shifts deserve a vet check.
