🐈 Scratching Post & Cat Tree Sizer
Most guides answer "how tall should a scratching post be?" with one generic number. Behaviourists answer it from your cat's own body: a post should be taller than your cat fully stretched. Measure once, and get your cat's real minimum height, base, platform and spacing — then check any product against them before you buy.
Your cat
Match the scratcher to the surface they already choose — a vertical scratcher offered a floor post mostly just relocates to your carpet.
The tree you're planning
Your cat's minimum sizes
🔍 Check a product before you buy it
Found a post or scratcher you like? Enter its scratching height (or length, for a flat scratcher) and we'll judge it against your cat — not a generic one. No size guide or shop does this; it's the whole reason posts get ignored.
📏 The full-stretch test (printable)
Don't trust our maths? Test it against the cat. This is the stand-in version of the behaviourist rule — and it's the final word before any purchase.
- Print this card and check the calibration bar below with a ruler — it must measure exactly 10 cm. If it doesn't, reprint at 100% scale ("Actual size", not "Fit to page").
- Tape a strip of paper to a wall (or use sticky notes) running from the floor up to the target height this tool gave you.
- Lure a full stretch: hold a treat or toy high on the wall so your cat stands on hind legs and reaches up with both front paws, claws out. Happy, bribed stretching only — never lift or pull a cat into position.
- Mark the highest claw reach. The top of the scratching surface on any post you buy should reach at least that mark — taller is fine, shorter is the #1 reason posts get ignored.
- For a flat scratcher: mark your cat's nose-to-tail-base length on the floor, add 10 cm, and check they can stretch along it.
My cat's target scratching height: – · body length: –
Why use this sizer?
Sized to your cat, not "a cat"
Every guide gives the same 30–36″ answer. Your cat's full-stretch length is the actual requirement, and it changes with the cat — a Maine Coon and a Singapura do not need the same post. This tool starts from your cat's body and works outwards.
Wobble-proof, not just tall enough
VCA Hospitals' warning, quoted in the behaviourist guides: a post that wobbles even once can be rejected permanently. So the result includes the base size and stability your cat's weight demands — height alone doesn't make a post usable.
A verdict on the exact product
The product checker judges a real post's height against your real cat and names the shortfall in centimetres and inches. Shops will never tell you a size is wrong for your cat. This page will.
How the numbers work — and where the guides disagree
Honesty first: the sources do not agree, and we'd rather show you that than hide it.
| Rule | What the sources say |
|---|---|
| Post height | Common buying guides and DIY plans say posts of 24–32″ are enough. The behaviourist buying guide (Liger), citing the AAFP, sets the bar higher: taller than the cat's full body length, with surveys pointing to a minimum ~3 ft (90 cm) for an adult cat; the CVMA phrases it as taller than the cat standing on hind legs. We use the behaviourist rule — because a too-short post is the most common reason cats ignore the post and keep the sofa, and a taller post harms nothing. |
| Full-stretch length | Your cat's stretch target = body length (nose to tail base) + front-leg reach (about 35 cm on a typical cat). Cross-check: cat-tree maker Kikska requires an uninterrupted scratch section of at least 80 cm for a full stretch — exactly a typical 45 cm cat plus reach. |
| Base size | Behaviourist guideline: about a 40 × 40 cm base for a 75 cm post, scaled up as posts get taller. For trees, DIY guide Aosom's bands: 2–3 ft tall → 18×18″; 4–6 ft → 24×24″; 6–7 ft → 30×30″. |
| Platforms & spacing | Platforms: 12×12″ minimum, 14×18″ for large breeds, 10×10″ for kittens (Aosom). Level spacing: about 40 cm for adults (Kikska); tighter 20–30 cm steps for kittens and seniors (Liger life-stage table). Resting spots and posts: one per cat, plus one. |
Material: sisal fabric is the behaviourist first choice (AAFP texture guidance via Liger) — sisal rope is a fine second; be wary of carpet-covered posts, since carpet loops can snag claws and feel too much like the carpet you're protecting.
Questions people ask
How tall should a scratching post be, in one number?
For an average adult cat: about 90 cm (roughly 3 ft) of scratching height — taller than the cat fully stretched on hind legs, per the AAFP-based behaviourist rule. Shorter guides saying 24–32″ describe the minimum many cats tolerate, not the length that lets a cat stretch properly. Use the sizer above for your own cat's number.
My cat scratches the carpet, not furniture legs. Does height still matter?
Orientation matters more than height for you: a carpet scratcher is a horizontal scratcher, so buy a flat or low-angled scratcher at least their body length + 10 cm long, and put it where the carpet crime happens. Offering a tall post to a committed horizontal scratcher usually just leaves you with both problems.
Why did my cat ignore the last post I bought?
The three classic causes, in order: too short to stretch on (the cat can't get a proper scratch, so the sofa wins), it wobbles (one wobble can put a cat off a post for good — check the base size in your result), or wrong orientation/material for their style. This tool is built to rule out all three before you spend anything.
How many scratching posts do I need for two cats?
Follow the n+1 rule used by the Ohio State Indoor Pet Initiative and the behaviourist guides: one scratching post per cat, plus one extra — so three posts for two cats, in different spots, with resting spots on a tree counted the same way. Shared territory goes much more smoothly with a spare.
What changes for a senior cat?
Comfort, not capability-shaming: floor-level or low horizontal scratchers first, ramps or close 20–30 cm steps instead of jumps on a tree, and a lower overall tree. The stretch still matters — it's how cats keep their claws and backs comfortable — it just shouldn't require an athletic leap to reach.
Keep exploring
Catio Planner — outdoor vertical space, sized properly too · Cat Home Safety Audit — where posts and trees should (and shouldn't) stand · Senior Cat Ramp Planner — the gentle way up for older cats · All KittyButts tools
Sizing guidance is based on published behaviour and buying-guide rules (AAFP guidance via the Liger buying guide, Kikska's layout guide, Aosom's DIY measurement tables). It's about comfort and behaviour — scratching is natural maintenance for claws and stretching — not medical advice. If scratching suddenly changes or a senior cat stops stretching, that's worth a conversation with your veterinarian.