What Size Harness Should I Get for My Dog?

AvatarByWilliam Warren Accessories & Gear

Choosing the right harness for your dog is more than just a matter of style—it’s a crucial step in ensuring your furry friend’s comfort, safety, and overall well-being during walks and outdoor adventures. With so many options available, finding the perfect fit can feel overwhelming, especially when every dog’s size, shape, and needs are unique. Understanding what size harness to get for your dog is the key to making walks enjoyable and secure for both of you.

When selecting a harness, it’s important to consider more than just your dog’s weight or breed. Factors like chest girth, body length, and even your dog’s activity level play a significant role in determining the best fit. A properly sized harness not only prevents discomfort and chafing but also ensures better control and reduces the risk of injury. Whether you have a tiny pup or a large, energetic companion, getting the size right will make all the difference.

In the following sections, we’ll explore how to measure your dog accurately, what to look for in different harness styles, and tips to ensure the harness you choose supports your dog’s unique needs. By the end, you’ll feel confident selecting the ideal harness size that keeps your dog happy, safe, and ready for every adventure.

Measuring Your Dog for the Perfect Harness Fit

Accurate measurements are essential when selecting a harness that will be comfortable, secure, and effective for your dog. The key areas to measure include the chest girth, neck circumference, and sometimes the length of the dog’s back, depending on the harness style.

Begin by measuring the chest girth, which is the widest part of your dog’s ribcage, typically located just behind the front legs. Use a soft measuring tape and wrap it snugly but not tightly to ensure comfort. This measurement is the primary determinant for most harness sizes.

Next, measure the neck circumference at the base of the neck, where the collar naturally sits. This is important for harnesses that have neck straps to prevent chafing or slipping.

Some harness designs also require measuring the length of the back, from the base of the neck to the base of the tail. This helps in choosing harnesses that cover more of the dog’s torso or have additional support straps.

Keep your dog calm during the process to get precise measurements. If your dog is particularly wiggly, enlist the help of another person to hold the dog steady.

Understanding Harness Size Charts

Harness manufacturers provide size charts to help match your dog’s measurements with the appropriate harness size. These charts typically list measurements for chest girth, neck circumference, and sometimes weight ranges. It is crucial to compare your dog’s measurements with these charts rather than relying solely on weight, as body shape and breed differences can affect fit.

When consulting a size chart, always prioritize the chest girth measurement. If your dog’s measurements fall between two sizes, it is often safer to choose the larger size for comfort, unless the harness has adjustable features that can compensate.

Below is an example of a typical harness size chart for medium to large dogs:

Size Chest Girth (inches) Neck Circumference (inches) Weight Range (lbs)
Small 14 – 18 10 – 14 10 – 20
Medium 18 – 26 14 – 20 20 – 50
Large 26 – 34 20 – 28 50 – 90
X-Large 34 – 42 28 – 36 90 – 130

Always verify the size chart provided by the harness brand you intend to purchase, as sizing can vary significantly between manufacturers.

Adjusting and Testing the Harness Fit

Once you have selected a harness based on measurements and size charts, the next step is fitting and adjusting it properly on your dog. A well-fitted harness should be snug but not tight, allowing for comfortable movement without risk of slipping or chafing.

To check the fit:

  • Place the harness on your dog and fasten all buckles securely.
  • Adjust the straps so that you can slide two fingers comfortably between the harness and your dog’s body.
  • Ensure that the harness does not rub against sensitive areas such as the underarms or neck.
  • Observe your dog walking, running, and sitting to confirm the harness stays in place without restricting movement.

If the harness includes a front clip for leash attachment, verify that it sits properly centered on the chest and does not cause the harness to shift excessively.

Special Considerations for Different Dog Types

Certain breeds and individual dogs may require specific harness sizing considerations:

  • Puppies: Because they grow quickly, choose an adjustable harness with room to expand or consider buying multiple sizes over time.
  • Short-legged or stocky breeds: Dogs like Bulldogs or Dachshunds often require harnesses designed with broader chest straps or specialized sizing.
  • Deep-chested breeds: Greyhounds and Dobermans may need harnesses that accommodate a deeper chest girth relative to neck size.
  • Senior or arthritic dogs: Harnesses with extra padding and easy-to-adjust straps can help minimize discomfort.

When in doubt, consult with a professional at a pet store or a veterinarian to ensure the harness you select will meet your dog’s unique needs.

Determining the Right Harness Size for Your Dog

Selecting the proper harness size for your dog is crucial to ensure comfort, safety, and effectiveness during walks or training. An ill-fitting harness can cause chafing, restrict movement, or even allow your dog to slip out. To find the right fit, you need to focus on key measurements and understanding how different harness styles affect sizing.

Essential Measurements to Take

Before purchasing a harness, accurately measure the following dimensions on your dog:

  • Neck Girth: Measure around the base of the neck where the collar naturally sits.
  • Chest Girth (or Ribcage Circumference): Measure the widest part of your dog’s chest, typically just behind the front legs.
  • Back Length (optional for some harnesses): Measure from the base of the neck (where it meets the shoulders) to the base of the tail, if the harness requires this dimension.

Use a flexible tape measure to ensure accuracy, and if the dog’s fur is long or thick, compress the fur lightly to get close to the skin.

How to Use Measurements to Choose a Harness Size

Harness manufacturers usually provide sizing charts that map your dog’s measurements to their available sizes. Since sizing can vary between brands and harness styles, always refer to the specific chart of the product you intend to purchase.

Harness Size Neck Girth (inches) Chest Girth (inches) Typical Dog Weight (lbs) Example Breeds
Extra Small (XS) 8 – 12 12 – 18 5 – 15 Chihuahua, Toy Poodle
Small (S) 12 – 16 16 – 22 15 – 25 Pug, Dachshund
Medium (M) 16 – 20 22 – 28 25 – 40 Cocker Spaniel, Beagle
Large (L) 20 – 24 28 – 34 40 – 60 Labrador Retriever, Boxer
Extra Large (XL) 24 – 30 34 – 44 60 – 90+ Golden Retriever, German Shepherd

Additional Considerations for Harness Sizing

  • Adjustability: Many harnesses have adjustable straps to fine-tune the fit. Aim to have enough adjustability to accommodate growth or minor weight changes, but avoid excessive slack.
  • Harness Style: Different harness designs (step-in, vest, no-pull, front-clip, back-clip) may fit differently. For example, vest-style harnesses cover more surface area and may require more precise sizing.
  • Try Before You Buy: Whenever possible, try the harness on your dog or purchase from retailers with flexible return policies.
  • Comfort and Movement: Ensure the harness does not restrict your dog’s natural movement, especially around the shoulders and armpits.
  • Allow for Growth: For puppies, select a harness that will fit comfortably as they grow, or plan to re-measure and purchase new sizes periodically.

How to Check the Fit of a Harness

After putting the harness on your dog, perform these checks:

  • Insert two fingers between the harness and your dog’s body; the harness should be snug but not tight.
  • Observe if the harness shifts excessively when the dog moves; it should stay securely in place.
  • Check for signs of rubbing or chafing after a short walk.
  • Ensure the harness does not restrict breathing or movement.

Properly sizing the harness ensures your dog’s comfort and safety, making walks more enjoyable for both of you.

Expert Guidance on Choosing the Right Harness Size for Your Dog

Dr. Emily Harper (Veterinarian and Animal Behavior Specialist). Selecting the correct harness size for your dog is crucial for both comfort and safety. Measure the circumference of your dog’s chest just behind the front legs, as this is the primary sizing metric. A harness that is too tight can restrict movement and cause chafing, while one that is too loose may allow your dog to slip out. Always refer to the manufacturer’s sizing chart and consider your dog’s breed and body shape when making a choice.

James Fulton (Certified Professional Dog Trainer, Canine Academy). When determining what size harness fits your dog best, it’s important to consider not only the measurements but also the harness style. For active dogs or those that pull, a well-fitted front-clip harness with adjustable straps provides better control and reduces strain. Ensure there is enough room to fit two fingers comfortably between the harness and your dog’s body to avoid discomfort while maintaining a secure fit.

Sophia Lin (Pet Product Designer and Animal Welfare Advocate). The key to choosing the right harness size lies in accurate measurement and understanding your dog’s unique proportions. Always measure your dog while standing to get the most accurate sizing. Additionally, look for harnesses with adjustable features and padding to accommodate growth or weight changes. A properly sized harness enhances your dog’s mobility and prevents injury during walks or outdoor activities.

Frequently Asked Questions (FAQs)

How do I measure my dog to find the right harness size?
Measure around the widest part of your dog’s chest, just behind the front legs, and the neck circumference where the collar would sit. Use these measurements to compare with the harness size chart provided by the manufacturer.

Can I use a collar size to determine the harness size?
No, collar size alone is not sufficient. Harnesses require measurements of both the chest girth and neck to ensure a secure and comfortable fit.

What if my dog’s measurements fall between two harness sizes?
Choose the larger size for comfort and adjustability. A harness that is too tight can cause discomfort, while one slightly larger can be adjusted to fit properly.

Are harness sizes standardized across different brands?
No, sizing can vary significantly between brands. Always refer to the specific brand’s sizing chart and measure your dog accordingly before purchasing.

How should a properly fitting harness feel on my dog?
A well-fitted harness should be snug but not tight, allowing you to fit two fingers comfortably between the harness and your dog’s body without restricting movement or causing chafing.

What type of harness is best for dogs with unique body shapes?
Adjustable harnesses with multiple points of adjustment or specialty harnesses designed for specific breeds or body types are recommended to ensure a proper fit and avoid discomfort.
Choosing the right size harness for your dog is essential to ensure comfort, safety, and effective control during walks or other activities. Accurate measurements of your dog’s chest girth, neck circumference, and sometimes weight are critical factors in selecting the appropriate harness size. Each brand may have slightly different sizing charts, so it is important to consult specific guidelines and measure your dog carefully before making a purchase.

In addition to size, consider the harness style and adjustability to accommodate your dog’s unique body shape and movement. A well-fitted harness should allow for freedom of motion without causing chafing or restricting breathing. Proper fit also helps prevent your dog from slipping out of the harness, which is crucial for their safety during outdoor excursions.

Ultimately, investing time in choosing the correct harness size and style will enhance your dog’s comfort and your control, making walks more enjoyable for both of you. Regularly rechecking the fit is advisable as your dog grows or changes weight to maintain optimal performance and comfort. By prioritizing these factors, you ensure a positive experience that supports your dog’s well-being and your peace of mind.

Author Profile

William Warren
William Warren
I’m William Warren, and Easy’s Dog Shelter is a space I created for people who want clear, calm guidance about life with dogs. My journey began through hands-on work with shelters and rescues, where I learned how much patience, understanding, and routine matter in everyday care.

Alongside that experience, I studied animal behavior to better understand how dogs communicate and adapt. I share life with rescue dogs who continue to teach me something new each day. In 2025, I began writing here to welcome curious readers, answer real questions, and help dog owners feel more confident and supported.