Your cat is cold at 21 °C: the thermoneutral zone and where to put the bed
Published by Planète Pets · managing editor: Clément Lacaille · how our guides are written
A heated home sits around 20 to 22 °C, a temperature calibrated on a naked primate. Cats work elsewhere: in a 2016 review in The Scientific World Journal, Stella and Croney note that a cat's thermoneutral zone is estimated at 30 to 38 °C, a value taken from National Research Council nutrient references (see the study). Our setup guides are gathered in the cat bedding and habitat section.
Contents · 4 sections
A gap of 8 to 16 °C with your living room
The thermoneutral zone is the range in which an animal holds its body temperature without spending extra energy. Below it, it spends. An indoor cat therefore lives permanently under the minimum comfort threshold — not in suffering, and the nuance matters, but in a state where seeking warmth becomes rational. That reframes behaviours we find amusing: sleeping on the router, on the laptop, above the radiator or in a patch of sun tracked from room to room is not a quirk, it is energy saving.
The seasonal trace in the food bowl
Serisier, Feugier, Delmotte, Biourge and German weighed the daily ration of 38 cats for four years and published their records in 2014 in PLOS ONE: intake fell to roughly 51-52 g a day in summer against 55-57 g in winter, close to 15 % less in June to August, peaking in January and bottoming in July (see the study). An honest caveat: the statistical analysis attributes the effect to day length rather than to temperature taken alone, the two being confounded. So those 15 % cannot be turned into thermal proof — only into a reminder that a cat's energy needs shift across the year.
Map the heat rather than heat the house
Neither source says to turn the thermostat up. The useful answer is local: multiply small warm zones instead of warming the air. In practice, a bed on an insulating surface, a box closed on three sides that traps body heat, a bed placed high where warm air settles, and clear access to the sunny spots of the day cover most of it. Our notes on an elevated or floor-level bed and on the heated bed extend the reasoning, bearing in mind that a kitten, an elderly cat or a thin cat tolerates the gap less well than a healthy adult.
- 30 to 38 °C: the reference thermoneutral zone for cats.
- 22 °C ± 2: typical indoor temperature, well below that range.
- Around 15 % less food in summer across 38 cats followed for four years.
- Effect attributed to photoperiod, not temperature alone: do not overread it.
A cat glued to the radiator is not reporting a heating fault but a physiology unlike yours: giving it three or four warm points spread around the home costs less than one more degree on the thermostat, and serves it better.
Frequently asked questions
At what temperature does an indoor cat start feeling cold?
No study sets a suffering threshold. We only know its reference thermoneutral zone starts around 30 °C, well above a heated home.
Why does my cat sleep on the router or the radiator?
Because those surfaces close the gap between room temperature and its comfort zone, sparing it the energy of staying warm.
Is a heated bed worth it, and how warm should it be?
It helps mainly kittens, elderly or thin cats. Choose a regulated model, placed where the cat can leave freely to avoid any overheating.
See it in the Planète Pets shop: Litter scoop with stand and bag roll in the handle (€20.90) · the whole shop
For your cat, at Le Félin (same family, zero commission): Arbre à chat XXL pour Maine Coon (from €139.99)
This guide is part of Planète Pets’s Cats universe. Our advice is general in nature: for any health concern, your veterinarian remains the only reference.