Size & Fit Guide
Sizing & Fit Guide to the Soul and Tail Products
How to measure your dog for a collar, harness, and leash — and how to choose gear that feels secure, comfortable, and ready for everyday movement.
Introduction
Choosing the right size dog gear is not only about matching a number on a chart.
A collar that is too loose can slip. A harness that is too tight will rub behind the front legs and restrict movement. A leash that is too short for an active day or too long for a busy sidewalk can make a simple walk feel harder than it needs to be. The right fit helps your dog move naturally and gives you confidence before the walk begins — especially when your dog is already at the door and ready to go.
At Soul and Tail, fit is part of how we design every product. It affects comfort, security, ease of use, and how naturally the gear works once you are actually outside. This guide walks you through how to measure your dog accurately, how to read the size charts, and how to think about collars, harnesses, and leashes as a complete setup rather than three separate decisions.
How to Measure
Measure While Your Dog Is Standing Naturally
The most accurate fit starts with your dog in a relaxed, natural position.
Use a soft measuring tape and keep it close to your dog's body without pulling it tight. Your dog should be standing with their weight evenly balanced — not sitting, lying down, or twisting toward the tape — because body shape changes in those positions, particularly around the chest and shoulders.
If your dog has a thick coat, measure over the coat without pressing the tape into the fur. The goal is not the smallest possible number. The goal is the measurement that reflects how the gear will actually sit during movement.
Breed examples in the size charts are a useful starting point, but they should never replace a real measurement. Dogs of the same breed can vary significantly by age, weight, coat thickness, and body shape. Two Border Collies of the same age can fit differently. A young dog and an adult dog of the same breed almost certainly will.
If your dog is moving around while you measure, do it twice and use the number that felt more natural. A calmer moment always gives a more reliable read.

Collar Fit
How to Measure for a Dog Collar
Neck girth is the primary measurement for choosing the right collar size.

Measure around the lower part of your dog's neck, where the collar naturally sits. The tape should rest close to the coat without pressing into the skin. Once the collar is on, a good fit means you can slide two fingers comfortably between the collar and your dog's neck — secure enough that it will not slip over the head, but not so snug that it presses into the neck during movement.
A well-fitted collar should sit steadily during a walk without shifting or hanging loosely. It should feel like it belongs there, not like something your dog is wearing.
| Size | Neck Girth | Width | Suggested Breeds |
|---|---|---|---|
| S | 10–14 in / 26–36 cm | 0.75 in / 2 cm | Toy Poodle, Maltese, Mini Dachshund |
| M | 14–20 in / 36–50 cm | 1 in / 2.5 cm | Border Collie, Corgi, Shiba Inu |
| L | 20–26 in / 50–66 cm | 1 in / 2.5 cm | Golden Retriever, Labrador Retriever, German Shepherd |
Breed examples are for reference only. Always measure your dog before choosing a size.
Harness Fit
How to Measure for a Dog Harness
Chest girth is the most important measurement when sizing a harness.

Measure around the widest part of your dog's chest, just behind the front legs. Keep the tape level around the body and avoid pulling it up into the armpit area. Chest girth matters because this is where the harness needs to distribute pressure and stay stable during movement — sitting, turning, jumping, and walking across uneven ground all put different demands on the fit.
Use both neck girth and chest girth when choosing a harness size, but lead with chest girth. Once you have selected the right size range, use the adjustment straps to fine-tune the neck and body fit so the harness sits flat and balanced.
| Size | Neck Girth | Chest Girth | Suggested Breeds |
|---|---|---|---|
| S | 11–16 in / 28–40 cm | 17–22 in / 44–56 cm | Shiba Inu, Mini Schnauzer, Small Corgi |
| M | 14–20 in / 36–50 cm | 21–27 in / 54–68 cm | Border Collie, Beagle, Cocker Spaniel |
| L | 18–26 in / 46–66 cm | 26–32 in / 66–82 cm | Australian Shepherd, Golden Retriever, Standard Poodle |
| XL | 20–31 in / 52–80 cm | 31–45 in / 80–115 cm | Labrador Retriever, German Shepherd, Bernese Mountain Dog |
Breed examples are for reference only. Always measure your dog before choosing a size.
Harness Check
What a Good Harness Fit Should Look Like
A well-fitted harness supports movement without limiting it.
Once adjusted, the harness should sit flat against your dog's body without twisting, bunching, or pressing into the armpit area. The back panel should lie evenly along the spine, and the chest piece should stay centered rather than sliding to one side during movement. You should be able to slide two fingers comfortably under any strap, but the harness should not shift noticeably when your dog walks, turns, or sits.
The chest area is the first thing to check. If the harness is riding too high toward the throat, or if the straps are pulling into the front legs, the sizing or adjustment needs to change. A harness that rubs consistently in one spot will become uncomfortable quickly, especially on longer walks.
For active dogs — dogs who pull, move across rough terrain, or change direction quickly — fit matters even more. Movement puts real stress on the harness structure, and a fit that feels fine on a short neighborhood walk may shift noticeably over a longer trail day.
The Daily Roam Harness is designed for everyday movement and regular walks, with a hinged structure that follows your dog's natural stride. The Trail Leap Harness is built for more demanding days outdoors, with wider panels, a belly strap for escape prevention, and a foam-padded lift handle for steep or technical terrain.

Between Sizes
What If Your Dog Is Between Sizes?
When measurements fall between two sizes, the right choice depends on where the overlap lands.
For collars, think about how the collar will be used day to day. If your dog is between sizes and has a thick coat, or if they are still growing, the larger size with the collar adjusted to fit is usually the more comfortable long-term choice. A collar with a little room to adjust is easier to live with than one that is already at the tightest setting.
For harnesses, prioritize chest girth above everything else. If your dog's chest girth falls in the lower end of the larger size, start there and use the adjustment straps to bring the fit in. A harness that is slightly generous in the chest but properly adjusted at the straps will always feel better than one that is pulling tight across the widest point.
Do not rely on breed examples to make the final call. Breed suggestions in the size chart are starting points, not guarantees. The measurements are what matter.
Leash Choice
Choosing the Right Leash
A leash does not fit the body, but it still needs to fit the way you move.
Leash selection is less about your dog's size and more about your daily routine and where your walks actually go. The two questions that matter most are how much distance you want between you and your dog during a typical walk, and whether you need your hands free at any point.
The Daily Step Leash is 5 feet long and designed for everyday use — city blocks, sidewalks, quick errands, and any walk where you want simple, close control. It works in four configurations: hand-held, crossbody, waist-worn, and short supervised tie-out.
The Trail Dash Leash runs from 7 feet 2 inches to 9 feet 2 inches with the bungee section extended. It is built for longer outings, more active movement, and trail days where your dog needs more room and your hands need to be free. The bungee section absorbs sudden pulls, and the dual padded handles give you close control when the terrain or situation calls for it.
Daily Step Leash
- Length
- 5 ft
- Best For
- Daily walks, city routines, closer control
- Handles
- Single padded main handle
- Clip
- Aluminum clip
- Bungee
- No
Trail Dash Leash
- Length
- 7 ft 2 in – 9 ft 2 in
- Best For
- Longer walks, trail days, active outdoor movement
- Handles
- Dual padded handles, main + traffic
- Clip
- Auto-lock aluminum carabiner
- Bungee
- Yes

Leash Modes
Four Ways to Use a Multi-Function Leash
Both leashes adjust between four modes depending on how your walk is going.
Hand-Held
Hand-held is the default for most walks. It gives you direct response and works well on sidewalks, near traffic, during training moments, or anywhere your dog needs to stay close.

Crossbody
Crossbody is for relaxed movement when you want your hands free but still want to feel connected. It works well on slower neighborhood walks, coffee runs, and casual daily routines where your dog is comfortable walking near you.

Waist-Worn
Waist-worn is for more active movement — light jogging, longer walks, or open trails where you and your dog can settle into a shared rhythm. This mode works best when your dog is comfortable at pace and the environment gives you both room to move. The Trail Dash Leash is the better choice for this mode, given its added length and bungee section.

Tie-Out
Tie-out is for short, supervised pauses only. Loop the leash around a fixed, weight-bearing object, click the buckle, and stay close. This mode is not designed for leaving a dog unattended — it is a brief hands-free pause, not a replacement for a proper tie-out setup.

The Experience
Fit is Part of the Experience
The right size helps the gear feel easier, safer, and more natural from the first snap.
Good dog gear is not only about materials or hardware. It is also about how the product fits your dog and how naturally it fits into your routine. A collar that sits right does not draw attention to itself. A harness that is properly sized stays where you put it. A leash that matches the pace of your walk feels like an extension of how you move together rather than something you are constantly managing.
When the fit is right, you spend less time adjusting and second-guessing, and more time outside with your dog. That is the experience every Soul and Tail product is designed to support — considered before the walk begins, dependable once you are out the door.

Find the Fit That Moves With Your Dog
Start with a simple measurement, then choose the gear that matches how you move together.
Measure your dog before choosing a size. Use neck girth as the primary guide for collars and chest girth as the primary guide for harnesses. When in doubt between two sizes, go up and adjust. Choose your leash based on the kind of walking you actually do, not the kind you occasionally plan to do.
A better fit makes every part of the routine feel easier: the first snap at the door, the first step outside, and the time you spend moving together after that.
Snap On. Go Explore.™