Pawhold Guides
Chest is the measurement that decides the size. Here is how to take it, what each Pawhold size covers, what to do when your cat falls between two, and how to check the fit once the harness is on.
Two measurements, and only one of them decides
You need the chest and the neck. The chest is the one that decides the size.
Weight is not a reliable guide. Two cats at the same weight can be built completely differently, and a long-haired cat measures larger than it is. A compact six-kilo cat and a rangy six-kilo cat need different sizes. Measure the cat rather than guessing from the scale.
Breed is not a shortcut either. There is more variation inside most breeds than between them, and most cats are not a breed at all.
How to measure your cat
Chest
Run a soft tape measure around the body just behind the front legs, at the widest part of the ribcage. Keep the tape flat and level, snug against the coat without compressing it.
Take the reading at the point where the tape just closes without dimpling the fur. If you pull hard enough to feel ribs you will read too small, and a harness ordered from that number will not close.
Neck
Measure around the base of the neck, where a collar would naturally sit, not high up under the jaw. High on the neck always reads smaller, and it is not where any strap actually rests.
The neck figure is a sanity check rather than the deciding number. If it falls outside the range for the size your chest measurement picked, measure both again before ordering.
If you do not have a soft tape
Use a piece of string or a shoelace. Run it around the cat, pinch where it meets, then lay it flat against a ruler. It is as accurate as a tape for this job and easier on a cat that dislikes the rustle of a tape measure.
Avoid a steel tape from a toolbox. It does not sit flat against a curved body and it reads long.
Measure a calm cat. A cat that is being held still tenses and flattens, which shortens the reading. Measure while your cat is standing and relaxed, and take the measurement twice. If the two readings differ by more than a centimetre, take a third.
Pawhold size chart
These are the chest and neck ranges for each size we sell. They are the same figures shown on the product page.
| Size | Chest | Neck | ||
|---|---|---|---|---|
| in | cm | in | cm | |
| S | 11.8 – 13.8 | 30 – 35 | 8.7 – 10.2 | 22 – 26 |
| M | 13.4 – 15.7 | 34 – 40 | 9.4 – 13.4 | 24 – 34 |
| L | 15 – 18.1 | 38 – 46 | 11.8 – 16.5 | 30 – 42 |
| XL | 16.5 – 20.5 | 42 – 52 | 14.2 – 19.7 | 36 – 50 |
The maker measures by hand and allows up to 2 cm (about ¾ in) either way. Chest is the measurement that decides the size.
Notice that the ranges overlap where two sizes meet. Each size has enough adjustment to cover a band of cats, which is why the number you measure matters more than the letter on the label. This harness runs small, so at the top of a range take the larger size.
What to do if your cat is between sizes
Choose the larger size. The ranges overlap on purpose, and a harness that is slightly large can be tightened down with its adjusters. One that is slightly small cannot be made bigger.
This is the opposite of the advice people expect, because a loose harness is what lets a cat escape. The difference is that a larger size adjusted correctly is still snug. A smaller size that does not close properly is not snug at all, it is simply unfastened.
There is one exception. If your chest measurement sits at the very bottom of a size and your cat is small and fine-boned, the smaller size will give you more adjustment range to work with. Sitting at the extreme end of any size is worth avoiding in either direction.
Checking the fit once it is on
Ordering the right size is half the job. The other half happens every time the harness goes on.
Slide two fingers flat under the strap. Two fingers, not two fingertips, and not a whole hand. Check at the neck strap and again at the chest strap, with the cat standing rather than held.
Cats flatten when they are picked up, and a harness fitted on a held cat is almost always too loose once the cat stands up again. If you can only manage that position, re-check the straps after you put the cat down.
Then do the reverse test. With the lead clipped and slack, let your cat take a step backwards indoors. If the rear strap slides forward toward the shoulders, it is too loose. Tighten and try again before you go anywhere. The full fitting sequence covers the order the straps should go on in.
Where each strap is supposed to sit
A size that measures correctly can still be worn in the wrong place, so it is worth knowing what you are aiming for before you adjust anything.
The neck strap
At the base of the neck, in front of the shoulders, sitting flat against the coat. Not up under the jaw, where it will ride and where a cat can paw at it. If the strap keeps creeping upward, it is too loose rather than too small.
The chest strap
Directly behind the front legs, around the widest part of the ribcage, and level on both sides. A chest strap that has slid backwards toward the waist has nothing to hold on to, because the body narrows behind the ribs. That is the single most common reason a correctly sized harness still comes off.
The lead ring
Centred on the back, between the shoulder blades. If it has slid round to one side the harness is twisted, and a twisted harness pulls unevenly the moment any weight goes on it.
Check all three with the cat standing, from the side and then from above. From above you should see a symmetrical shape with the ring in the middle.
Measuring a cat that will not cooperate
Some cats simply will not stand still for a tape measure. There are ways around it.
Measure at mealtime. A cat with its head in a bowl is standing, relaxed and stationary, which is exactly the position you need. Most measurements take about four seconds once the cat stops caring.
Split the job. Take the chest one day and the neck the next rather than turning it into a wrestling match that makes the cat suspicious of string forever.
Measure something the cat already wears. If your cat has a collar that fits well, measure the collar rather than the cat, at the setting it is currently on. The same trick works for a harness that fits, laid flat and measured strap by strap.
Ask for the reading at a vet visit. If your cat is going anyway, a chest measurement takes seconds and the cat is already being handled.
Coats, seasons and weight
A cat is not a fixed size, and a harness fitted once in July will not fit the same cat in January.
A thick winter coat adds real circumference. The straps end up sitting on hair rather than on the cat, which feels snug and is not. When the coat blows in spring the same setting becomes slack overnight. Re-check the adjusters at both ends of the shedding season.
Weight moves the fit too, in both directions, and a cat that has gained or lost even a few hundred grams can need a different setting. This is one more reason to check the straps before each outing rather than trusting the last one.
Long-haired cats are the hardest to measure. Do not try to press the tape down to the skin. Measure over the coat, snug but not compressing, and rely on the adjusters for the rest.
Kittens and growing cats
A kitten will outgrow its first harness. That is worth planning for rather than avoiding.
Fit the size that matches the measurements you take today. Buying ahead leaves slack now, and slack now is how a kitten backs out. Re-measure every few weeks while your kitten is growing, and check the fit before each walk rather than assuming last month's setting still holds.
Very small kittens are usually better off practising indoors until they measure into a size properly. Indoor practice is not a waste of time. It is the part of the process that decides whether the cat tolerates a harness at all, and it costs nothing to do it for an extra month.
Sizing a collar is a different job
A collar uses the neck measurement, not the chest, and it is adjusted to a different standard.
Our breakaway cat collar comes in one adjustable size, 7.5 to 12.6 in, and the range is printed on the product page alongside the strap width. Take the neck measurement the same way as above, at the base rather than under the jaw.
The two-finger rule applies here as well, and it matters more than it does on a harness. A collar loose enough for three fingers is loose enough for a cat to get a front leg through while grooming, and a cat with a leg caught through its collar is in real trouble. If your cat has never worn one, introduce the collar gradually rather than fastening it and hoping.
Five measuring mistakes
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Using weight instead of a tape. Build varies far too much for weight to predict a chest measurement.
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Measuring a held cat. Held cats flatten. Stand the cat up and measure again.
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Pulling the tape tight. Snug against the coat, not compressing it. A tight tape reads small and the harness will not close.
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Measuring the neck under the jaw. Measure at the base, where a strap actually rests.
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Buying a size up for a kitten to grow into. The extra room is exactly the slack a kitten reverses out of.
Once the size is right, the rest of the setup is straightforward: fit the harness indoors, clip the lead to the ring on the back, and keep it slack. If you are still deciding between a harness and a collar for walking, the comparison guide covers why the lead only ever goes on the harness.
FAQ
Which measurement matters most for a cat harness?
The chest. Measure around the body just behind the front legs, at the widest part of the ribcage. The neck measurement is a secondary check.
What if my cat is between two sizes?
Take the larger size. A slightly large harness can be tightened with its adjusters, while a slightly small one cannot be made bigger.
Can I use my cat's weight to pick a size?
No. Cats of the same weight can be built very differently, and long coats make a cat look larger than it measures. Use a tape or a piece of string instead.
How do I measure a cat that will not sit still?
Measure while your cat is standing and relaxed rather than held, take the reading twice, and use a piece of string against a ruler if a soft tape is awkward.
Should I buy a bigger harness for a kitten to grow into?
No. Extra room is what lets a kitten back out. Fit the measurements you take today and re-measure every few weeks while your kitten grows.
How tight should a cat harness be?
Two fingers should slide flat under the strap, checked at the neck and at the chest with the cat standing. Two fingertips is too tight and a whole hand is too loose.
Does a thick winter coat change the size I need?
It changes the setting rather than the size. Measure over the coat without compressing it, then re-check the adjusters when the coat thins out in spring.
Is a collar sized the same way as a harness?
No. A collar is sized from the neck measurement, taken at the base of the neck. A harness is sized from the chest.
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