Australian Shepherd harness size chart: 24–34 in chest

How do I measure an Australian Shepherd for a harness?

1. Stand the dog square. Use a soft tape around the deepest part of the ribcage, just behind the front legs.
2. Keep the tape level and snug, then leave room for two fingers under the chest strap.
3. Do not use neck circumference for the chest band. Neck and girth are different numbers.
4. Pick the smallest chart size whose maximum girth still covers your tape plus about one inch of ease.

What harness fit notes matter for an Australian Shepherd?

A harness for an Australian Shepherd is sized from chest girth, not from neck circumference. Typical adult chests sit around 24–34 inches at the deepest rib, behind the front legs. Leave about 1 inch of ease so two fingers fit under the strap.

At the low end of that range, expect the medium band (22–28 in chest). At the high end, expect the large band (28–36 in chest). One Australian Shepherd does not size the next—the tape replaces the breed name.

The build to expect is a medium neck under a double coat that thickens in winter. A common miss on harnesses for this shape is related to how people already mishandle the neck: using a winter coat measurement for a summer cut. For the chest strap, keep the tape level and on the ribs, not on the coat.

Remeasure when the undercoat blows. The skin number is what the knot feels. If the strap sits on the soft belly or slides into the armpits, remeasure the deepest rib and move up or down one band—do not yank the neck strap tighter to compensate.

Chest girth and neck circumference are different measurements. Use the rib tape for harness bands; use the collar line for tied bandanas on the bandana calculator.