How to Measure Your Dog for a Collar or Harness

A size name such as Small or Medium is not a measurement. Two harness styles can use the same size letter for different neck and chest ranges, so the reliable starting point is to measure your dog and compare those numbers with the chart on the exact product page.

You need a soft measuring tape, your dog standing naturally, and the product chart you plan to use. If you do not have a soft tape, place a non-stretch string around the measurement path, mark the overlap, and measure the string flat with a ruler.

Dachshund diagram showing neck, harness-neck, and chest-girth measurement locations.
This illustration shows general measurement locations, not a specific product fit. Harness construction varies; use the exact product chart and recheck the fitted gear.

Take the two key measurements

  1. Neck: place the tape around the part of the neck where the collar normally rests. For a harness, follow the neck path shown in that model’s size guide rather than measuring high under the jaw.
  2. Chest girth: with your dog standing, wrap the tape around the widest part of the rib cage, usually just behind the front legs. Keep the tape level around the body.
  3. Record the number: write down the measurement in inches and centimeters if your tape shows both. Do not round to a familiar size letter.
  4. Repeat: take each measurement a second time. If the results differ, reposition the tape and measure again before choosing.

The tape should follow the body without squeezing it. Thick or long fur can change how the tape sits, so part the coat enough to find the measurement path without compressing the dog’s body.

For a collar

Use the neck measurement and compare it with the adjustable range listed for the exact collar. Do not choose from breed, age, or weight alone. Our print collars are grouped in the Collars collection, including the Pumpkin Print Dog Collar and Leaf Print Dog Collar.

After the collar arrives, adjust it according to its product directions. Check that it is not pressing tightly into the neck and does not slide over the dog’s head during ordinary movement. Recheck the fit after grooming, coat changes, or growth, and inspect the buckle, adjustment points, and leash ring before use.

For a harness

Harness sizing usually depends on chest girth and may also use the neck measurement. Compare both numbers with the exact chart for the model you are buying. If the two measurements do not clearly fall within one listed size, do not guess from the size name; review that product’s chart again before ordering.

This matters in our own assortment. The Candy Color harness uses an XS–L chart, while the Colorblock harness uses a separate S–XL chart. A Medium in one model should not be assumed to match a Medium in the other. See the chart in the gallery of the exact product, such as the Blue Candy Color Dog Harness or Green Colorblock Dog Harness.

Check the fit after adjustment

  • Follow the product’s fitting directions and adjust each available strap.
  • Check the fit while your dog is standing and moving normally.
  • Look for straps pressing at the throat, rubbing behind the front legs, or limiting shoulder movement.
  • Gently check the harness in different directions to see whether your dog could back out of it.
  • Stop and readjust if you notice rubbing, pinching, restricted movement, or damaged hardware.

Measurements narrow the choices; the model-specific chart and the fitted check finish the job. Browse all current colors and both chart families in Dog Harnesses.

Next: Once the fit is sorted, use How to Choose the Right Dog Leash Length to match the leash range to the setting.