Are your fingerprints really unique?

Fingerprints have long been known to be unique. They also don’t change their pattern over your lifetime, making them an extremely useful biometric for identification. Their uniqueness largely comes from how they form in the womb: as waves of skin cells growing in random patterns of ridges under the top layer of skin in our hands and feet.

Fingerprints are so unique that it is considered impossible to match two different fingerprints from the same person — the only way to know for sure is to match a fingerprint to the exact finger. But a new AI tool developed by students at Columbia University demonstrates there are more similarities in intra-person, or same-person, fingerprints than we’ve previously known.

In this video, we break down how fingerprints form and how a new AI tool might be changing how we think about their patterns.