Normally, cats have 18 toes—five on each front paw and four on each back paw. This usually includes a dewclaw on each front paw but not on the back.

“Polydactyly” refers to the presence of extra digits, even if it’s just one additional toe or an extra dewclaw. “Extra toes can be found on the front or hind limbs,” Patel says.

It’s most common for extra toes to form on the inside of the paw, which is the pre-axial (or thumb) side. Less commonly, extra digits form on the outside of the paw (the post-axial or pinky side) or meso-axial (in the middle). Extra digits don’t always come in pairs, meaning your cat’s paws could be asymmetrical.

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