Getting the size right matters more than which brand you choose.
Measuring for a harness
You need chest girth: measure around the widest part of the ribcage, just behind the front legs, with the tape snug but not compressing the fur. Take the measurement with the dog standing, not sitting.
Some brands also want neck girth — measure where a collar would naturally sit, not at the base of the skull.
Weight is a poor guide on its own. A forty-pound whippet and a forty-pound bulldog need different harnesses entirely.
If you're between sizes
Size up for a growing dog or a thick winter coat. Size down for a lean, short-coated dog. If you're genuinely unsure, email us the measurements and the breed and we'll tell you what we'd order.
Checking the fit
Two fingers should slide flat under any strap. If you can pull the harness over the dog's head with the buckles done up, it's too loose. If the dog's gait changes when wearing it, the shoulder straps are sitting wrong.