A harness should feel like it was made for your dog, snug enough to stay put, loose enough to move freely, and never rubbing. The good news is that getting the fit right takes two measurements and about two minutes. Here’s exactly how, plus how to pick the style that suits your dog best.
How to measure your dog for a harness
You need two measurements, both taken with a soft tape measure (or a piece of string you then hold against a ruler). Measure your dog standing up, not sitting.
- Chest girth — the big one. Measure right around the widest part of the ribcage, just behind the front legs.
- Neck girth — measure around the lower neck, slightly lower than where a collar would naturally sit, at its widest point.
The two-finger rule: keep the tape snug but not tight — you should be able to slide two fingers flat underneath. That’s the sweet spot between secure and comfortable.
Write both numbers down, then check them against the size chart below. If your dog is still growing, measure again every few weeks, a puppy’s chest changes fast.
Choosing your size
Our harnesses come in five sizes, XS to XL, and adjust at both the neck and chest for a tailored fit.
| Size | Chest girth | Neck girth |
|---|---|---|
| XS | 38 – 56 cm | 34 – 44 cm |
| S | 54 – 70 cm | 37 – 50 cm |
| M | 60 – 76 cm | 42 – 52 cm |
| L | 71 – 88 cm | 45 – 57 cm |
| XL | 77 – 99 cm | 52 – 73 cm |
Not sure which size to choose? We’re here to help! Since dogs come in all shapes and sizes, breed alone isn’t always a reliable guide. In fact, two Cockapoos of the same breed can measure completely differently! To get the perfect fit, always measure your dog with a tape measure instead of relying on standard size labels.
If you’d like support with sizing, ordering through Find the Fit is the quickest way to get set up! Simply select “Yes please” for sizing support when adding your harness or set to the basket. After checkout, you’ll be invited to upload your dog’s measurements and photos. Our team personally reviews everything before sending your order out, ensuring a flawless fit every time!
Y-shape vs H-shape: why the shape matters
Not all harnesses sit the same way, and the shape makes a real difference to your dog’s comfort and safety.
An H-shape harness has a strap straight across the front of the chest. When your dog pulls, that strap presses into the shoulders and restricts the natural swing of their front legs.
A Y-shape harness, the shape we make, sits lower, forming a Y over the chest. It spreads pressure across the sternum and leaves the shoulders free to move. So when your dog pulls, there’s no jolt to the neck or airway and no rubbing at the shoulders. Just a safer, more comfortable walk, whether you’ve got a gentle plodder or an enthusiastic puller.
Ours are finished with breathable padded mesh, soft anti-chafe lining and reflective stitching for early-morning and after-dark walks.
Front clip or back clip?
Every Pawshtails harness has two lead attachment points, and each has its moment.
- Front clip (on the chest) — your training tool. When your dog surges ahead, a lead clipped to the front gently turns them back towards you, which takes the power out of a pull. Ideal for dogs still learning not to tow you down the street. Please note: This tool supports your walks, but active training is still required.
- Back clip (between the shoulders) — your everyday default. Relaxed, unrestricted, perfect for dogs who already walk nicely or for calm strolls where there’s nothing to redirect.
A good rule of thumb, stick to the front clip while you’re actively working on pulling, and move to the back clip once your dog is walking nicely by your side. Pair the front attachment with a short lead and plenty of treat rewards, and you’ll likely see fantastic progress in just a couple of weeks!
Still not sure? We’ll size your dog for you
We know how tricky measuring an excited pup can be, and we want to help you avoid the hassle of returns.
For the quickest turnaround, order through Find the Fit page here and select “Yes please” to sizing support. Once checkout is complete, you’ll be asked to submit your measurements and dog photos. Don’t worry about paying upfront, our team verifies every size before dispatching your order, so you’re guaranteed a flawless fit!
Prefer to double-check first? Feel free to send your dog’s photos and measurements to [email protected] and we’ll help you pick the perfect size before you buy. Please note this may take 1-3 days during busy periods.
Harness Sizing FAQs
How do I measure my dog for a harness?
Measure two things with a soft tape: chest girth (around the widest part of the ribcage, just behind the front legs) and neck girth (the widest part of the lower neck). Keep it snug enough to slide two fingers underneath, then match your chest measurement to the size chart.
My dog is between two sizes, which do I choose?
For about 90% of dogs, we recommend choosing the smaller size, as our harnesses are generously adjustable.
However, every dog is unique! If you’d like us to confirm the perfect fit, you have two options:
- Email Us First: Prefer to check before buying? Send your dog's photos AND measurements to [email protected], and we’ll confirm the best size before you place an order.
- Fastest Way: Order using our Find the Fit link here and select "Yes please" for sizing support. Right after checkout, you'll be prompted to enter your dog's measurements and upload photos. Our experts personally verify every detail before shipping, so it's 100% risk-free!
Is a Y-shape harness better than a strap harness?
Yes. A Y-shape sits lower on the chest and spreads pressure across the sternum, leaving the shoulders free and keeping pressure off the neck and airway when your dog pulls. An H-shape strap presses into the shoulders and restricts movement.
Will the harness rub my dog's fur?
No, it's lined with soft, breathable anti-chafe padding all the way around, and adjusts at both the neck and belly for a smooth, secure fit.
Is the harness overhead or step-in?
Our harness slips over your dog’s head and fastens securely with buckles on either side of the chest. Please note, it does not have a neck buckle.
Over 99% of dogs are completely happy with this style, as it's quick and easy to pop on! However, if your dog is particularly head-sensitive, we always recommend getting them used to the harness gradually using positive reinforcement and treats.
What if it doesn't fit when it arrives?
We offer 14-day returns on unworn harnesses, and free sizing help before you order so it fits first time. Send us a photo and your measurements and we'll pick the size for you.
