Choosing the right harness size is one of the easiest ways to make walks more comfortable, safer, and more enjoyable for your dog.

A harness that is too tight can cause rubbing and restrict movement, while one that is too loose may shift around or even allow your dog to slip out during walks.

The good news? Measuring your dog for a harness only takes a few minutes and can help you choose the right size first time.

Whether you're shopping for your first harness or replacing an old one, measuring your dog correctly can help prevent discomfort, rubbing, and sizing mistakes. This guide explains how to measure a dog for a harness in the UK and how to choose the right fit for everyday walks.

What You'll Need

Before you start, grab:

• A soft tape measure

• A few treats to keep your dog relaxed

• A pen or phone to note measurements

• A calm standing position for your dog

Don't have a tape measure? A piece of string and a ruler will work just as well.

Step 1: Measure Your Dog's Chest

For most dog harnesses, the chest measurement is the most important measurement.

The chest girth is measured around the widest part of your dog's chest, just behind their front legs.

How To Measure Chest Girth

1. Ask your dog to stand naturally.

2. Wrap the tape measure around the widest part of their chest.

3. Keep the tape snug but not tight.

4. Record the measurement in centimetres.

Tip: You should be able to comfortably fit two fingers between the tape measure and your dog's body.

Step 2: Measure Your Dog's Neck

Some harness styles also use neck measurements to help achieve the best fit.

Measure around the base of your dog's neck where a collar would naturally sit.

Avoid measuring too high up near the head, as this can result in an inaccurate size.

Step 3: Check Your Dog's Weight

While measurements should always be your primary guide, knowing your dog's weight can be useful when comparing sizing recommendations.

Remember that dogs of the same breed and weight can have very different body shapes, so always prioritise actual measurements over weight alone.

Common Harness Measuring Mistakes

Using Weight Instead Of Measurements

One of the most common mistakes is choosing a harness based purely on weight.

For example, two Cockapoos weighing the same can have completely different chest sizes.

Always use measurements first.

Measuring Too Loosely

A loose tape measure can result in ordering a harness that's too large.

The tape should sit comfortably against your dog's body without squeezing.

Measuring Over Thick Clothing

If your dog wears a coat or jumper during colder months, take measurements without bulky clothing underneath for the most accurate result.

What If Your Dog Is Between Sizes?

If your dog's measurements fall between two sizes, we generally recommend choosing the larger size.

Most adjustable dog harnesses can be tightened for a secure and comfortable fit while giving your dog room to move naturally.

How Should A Dog Harness Fit?

A properly fitted harness should:

• Allow full shoulder movement

• Sit comfortably without rubbing

• Stay secure during walks

• Allow two fingers to fit underneath the straps

• Remain in place without twisting or slipping

Your dog should be able to walk, run, play, and explore comfortably while wearing their harness.

Why Adjustable Harnesses Are So Popular

Adjustable dog harnesses have become a favourite among dog owners because they offer flexibility, comfort, and a more customised fit.

They're particularly useful for:

• Growing puppies

• Dogs with broad chests

• Dogs between sizes

• Active dogs who love exploring

A well-fitted adjustable harness can help make daily walks more enjoyable for both you and your dog. If you're looking for a no-pull option with a secure, adjustable fit, our Urban Rover style harnesses are a popular choice for active dogs and everyday adventures.

Dog Harness Size Guide By Breed

While measurements are always more accurate than breed recommendations, the examples below can provide a useful starting point:

• Chihuahua – Usually XS

• Yorkshire Terrier – Usually XS-S

• Miniature Dachshund – Usually S

• Cockapoo – Usually S-M

• Cocker Spaniel – Usually M

• Border Collie – Usually M-L

• Labrador Retriever – Usually L

• Golden Retriever – Usually L

• German Shepherd – Usually XL

Always check your dog's actual measurements before choosing a harness size.

Measuring Puppies For A Harness

Puppies grow quickly, so it's worth checking their measurements regularly during the first year.

An adjustable harness is often the best choice for puppies as it allows room for growth while maintaining a comfortable and secure fit.

Remember to remeasure your puppy every few months to ensure their harness still fits correctly.

Finding The Right Harness For Your Dog

At For Dog Lovers, we believe beautiful dog essentials should be comfortable, practical, and accessible.

Our adjustable dog harnesses are designed with everyday adventures in mind, offering:

• Adjustable straps for a secure fit

• Lightweight comfort

• Durable materials

• Matching collars, leads and accessories

• Quality and style without the premium price tag

Looking for a no-pull harness with a structured, urban-ready design? Explore our Urban Rover no-pull harness collection — built for dogs who mean business on their walks.

Because we know how much you love them.

Complete The Look With Matching Walking Essentials

Many dog owners love creating coordinated walking sets that combine comfort, practicality, and style.

Explore our matching collection of dog harnesses, collars, leads, poo bag holders and complete dog walking sets — saving 30% vs buying separately.

Whether you're heading out for a quick stroll or a weekend adventure, matching accessories can help make every walk feel that little bit more special.

Frequently Asked Questions

What Is The Most Important Measurement For A Dog Harness?

The chest girth measurement is usually the most important measurement when choosing a dog harness, as it determines how securely the harness fits around your dog's body.

How Tight Should A Dog Harness Be?

A harness should be snug enough to stay secure but loose enough for you to fit two fingers comfortably underneath the straps.

Can I Choose A Harness Size Based On Breed?

Breed guides can be helpful, but measurements are always more accurate. Dogs within the same breed often vary significantly in size and shape.

Are Adjustable Harnesses Better?

Adjustable harnesses offer greater flexibility and can help achieve a more secure fit, especially for dogs who are between sizes or still growing.

Final Thoughts

Taking a few minutes to measure your dog properly can make a huge difference to their comfort and safety on walks.

By measuring your dog's chest, checking their neck size, and choosing an adjustable fit where possible, you'll be well on your way to finding a harness that both you and your dog will love.

After all, every happy adventure starts with the right fit.

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