How much should a King Charles weigh?

Most Cavalier King Charles Spaniels land between about 5.9 and 8.2 kg once they're fully grown, usually around 12 to 18 months. That's a decent spread, and a lean 8 kg Cavalier with a bit of frame on them is in better shape than a soft 6.5 kg one. So the weight on the scales is only half the picture.

The better test takes ten seconds. Run a flat hand along their ribs. You should feel them easily under a thin covering, roughly like the back of your knuckles when your hand is relaxed. If the ribs are sharp and obvious, they're carrying too little. If you have to press to find them, they're carrying too much. Look down at them from above for a waist behind the ribs, and from the side for a belly that tucks up rather than running straight through.

Cavaliers are a breed that will happily eat whatever's going and then have a nap about it. That combination adds up quietly. Weighing food on kitchen scales instead of scooping it, and counting treats inside the daily total, does most of the work.

If your Cavalier is gaining or losing weight without any change to their food or exercise, talk to your vet. Sudden shifts are worth checking properly rather than adjusting the bowl and hoping.