A cat has 18 toes: 5 on each front paw and 4 on each rear. A total of 19 or more is polydactyly, and in most cases the extra digit sits on the inner, thumb side of a front paw. The trait runs in family lines, is harmless in most cats, and creates one real job for the owner: the extra claw never touches the floor, so it never wears down. Count all 4 paws, dewclaws included, and write the total in the record before the first vet visit.
Three presentations, three different problems
Polydactyly gets sorted by where the extra digit sits and how it is built, and the 3 groups behave differently at home. The preaxial thumb sits on the inner edge of a front paw with its own claw, pad and usually its own metacarpal; 1 extra toe gives 6 on that paw, the double form gives 7, and both are stable, weight-bearing structures that rarely cause trouble beyond nail care. The postaxial type sits on the outer edge, most often on a rear paw where the normal count is 4, and is usually fully formed.
The fused or webbed type is where the problems live: 2 digits share 1 pad or 1 metacarpal that forks in a Y, so the paw snags on carpet, packs litter between the toes and hides a claw where nobody looks. Such a digit may have no bony attachment and hang by skin alone. Any of the 3 can be unilateral or present on all 4 paws, and the unilateral cases are the ones missed for years, because owners count the paw they happen to be holding.
Count 4 paws, twice
Put the cat on a non-slip surface in good light and count paw by paw, spreading the toes with a thumb. Each front paw carries 5 toes plus 1 dewclaw set higher on the inner leg; the dewclaw is not part of the 18 and is the most common counting error. Each rear paw carries 4, and a rear paw with 5 is the finding that goes unnoticed the longest.
Run the pass twice, 10 minutes apart. Photograph the underside of each paw flat on a table, 1 photo per paw, and keep the set: in 12 months that photo tells you whether a floppy digit is drifting or stable.
What a radiograph answers, and when to take it
An X-ray is not needed to diagnose polydactyly; the toes are visible to anyone who counts. It answers 1 question: does the extra digit have its own bone, and does that bone articulate with a metacarpal or float in soft tissue. That answer decides between trimming a claw for 15 years and removing a digit at 4 months. Below 4 months the digit is largely cartilage and the film is close to unreadable; the useful window is 4 to 6 months, when ossification is far enough along to trace the metacarpal and the growth plates are still open and obvious. If surgery is planned, a second set at 12 months gives an adult baseline, since those plates close around 6 to 8 months.
Ask for 2 views of the affected paw, dorsopalmar and lateral, with 1 marker for side. A single view hides a digit that overlaps its neighbour, and the lateral is the only one that shows a Y-shaped fork. The same eye reads a chest film the same way.
The claw that never meets the floor
A normal cat wears its claws down on flooring, scratching posts and prey. An extra digit sits above the pad at an angle, so its claw keeps growing at roughly 1 to 2 mm a month and curves inward. A kitten with an extra digit needs a trim every 2 to 3 weeks from 6 weeks of age; an adult with a normal 18-toe foot can go 6 to 8 weeks, the polydactyl adult needs every 3 to 4 weeks, the double form every 2. Press the pad flat and look into the groove between the extra digit and its neighbour to find the tip.
Signs the claw has already pierced the pad: a 1 to 2 mm dark spot on the pad, 1 paw licked more than the other 3, a flinch when that paw is held, a faint blood spot on the floor after a jump down. Clean twice a day for 5 to 7 days, and book a visit if the cat is lame past 48 hours or the pad is swollen.
When removal is the right call
Most extra digits stay for life. Removal gets considered in 3 situations: the digit has no bony attachment and flops; 2 digits share a pad so deeply that litter and hair pack in and cannot be cleaned out; or the claw cannot be trimmed without pain. The usual window is 3 to 5 months, old enough for a short anaesthetic, young enough that the kitten forgets the paw. A simple removal heals in 10 to 14 days: soft bandage for 3 to 5 days, cone for 10 to 14 days, sutures out at 10 to 14 days, no jumping for 2 weeks. Removing a digit with a normal, weight-bearing metacarpal is a different operation, with 4 to 6 weeks of healing and a real chance of a permanently altered gait.
Inheritance is simple, registry rules are not
The trait is autosomal dominant with variable expressivity. One copy of the allele is enough, the same sire can produce 19-toe and 18-toe kittens in 1 litter, and a cat with 18 toes out of a mitten line can still carry the allele and pass it on. The homozygous state is widely described as lethal before birth. Registration is where owners get surprised: some registries disqualify polydactyly in most breeds, others accept it as a permitted variant,. None of that changes the cat's health; 3 minutes with a trimmer every 3 weeks does. If you are checking whether a cat matches a breed standard rather than a colour pattern, a short breed quiz beats reading 5 standards.
| Type | Typical toes on that paw | Bone under it | Film timing | Removal rate |
|---|---|---|---|---|
| Preaxial thumb, 1 side | 6 | Own metacarpal in most cases | 4 to 6 months | Low |
| Preaxial, both sides or 4 paws | 6 to 7 | 1 or 2 own metacarpals | 4 to 6 months | Low |
| Double thumb (mitten) | 7 to 8 | 2 metacarpals, fused at base | 4 to 6 months | Sometimes |
| Fused or webbed | 6, sharing a pad | Shared or absent | 3 to 5 months | Often |
| Postaxial, rear paw | 5 | Own metatarsal | 4 to 6 months | Low |
A 5-minute check, once a month
Run the same 5 steps on the same date each month.
- Count all 4 paws out loud, front left to rear right, and say the total.
- Press each pad flat and look for a 1 to 2 mm dark spot or a red groove.
- Trim the extra claws, then feel each tip for a hook.
- Photograph the 2 paws that carry extra digits, same angle every time.
- Watch the cat walk 10 steps on carpet and note any hop or skip.
Terms mentioned in this article
Frequently asked
How many toes does a normal cat have?
A normal cat has 18 toes in total: 5 on each front paw and 4 on each rear paw. The dewclaw on the inside of each front leg sits higher up and is not counted in that 18. A cat with 19 or more is polydactyl, and a rear paw carrying 5 toes instead of 4 is the version owners most often miss for years, because the front paws get all the attention.
Does polydactyly cause health problems in cats?
For most cats the extra digit causes no problem beyond nail care. The claw does not touch the floor, so it does not wear down and can curl into the pad within weeks if it is left alone. Trouble is concentrated in the fused type, where 2 digits share a pad and trap litter, and in digits with no bony attachment that snag on carpet. Trim the extra claws every 2 to 4 weeks and most polydactyl cats live ordinary lives.
At what age should a polydactyl kitten be X-rayed?
The useful window is 4 to 6 months. Before 4 months the extra digit is mostly cartilage and the film will not tell you whether it has its own metacarpal, which is the only question the X-ray needs to answer. If surgery is being planned, a second set at 12 months gives an adult baseline, since the growth plates in the extra digit close somewhere around 6 to 8 months of age.