Chest girth is what counts
Harnesses are sized mainly by chest girth — the measurement around the widest part of the ribcage, just behind the front legs. Wrap a soft tape snugly (not tight) and note the number. Neck girth is a useful secondary check, but chest is the one that determines whether a harness fits.
Harness size chart
| Size | Chest girth | Typical dog |
|---|---|---|
| XXS | 9–13″ | Chihuahua, toy breeds |
| XS | 13–18″ | Yorkie, Pomeranian |
| S | 18–22″ | Pug, small terrier |
| M | 22–28″ | Beagle, Cocker Spaniel |
| L | 28–34″ | Labrador, Boxer |
| XL | 34–42″ | German Shepherd, Rottweiler |
Bands are typical, not universal — every brand sizes a little differently.
Frequently asked questions
- How do I measure my dog for a harness?
- Measure the chest (girth) around the widest part of the ribcage, just behind the front legs, with the tape snug but not tight. That measurement is what most harness sizes are based on. It also helps to measure the neck girth where a collar sits.
- What if my dog is between harness sizes?
- Size up. A slightly larger harness can be tightened with its adjustment straps, but one that’s too small will rub and restrict movement. A good fit lets you slip two fingers under any strap.
- Do harness sizes vary between brands?
- Yes — a “medium” from one brand can differ by several inches from another. Always measure your dog and check the specific brand’s size chart rather than relying on size letters alone.
- Should I use my dog’s weight to choose a harness?
- Weight is only a rough guide — two dogs of the same weight can have very different chest sizes. Measure the chest girth for an accurate fit; use weight only as a sanity check.
Sizing differs between brands — always measure your dog and check the specific harness’s size chart. When in doubt, size up and use the adjustment straps for a snug, two-finger fit.