You have two pictures and one question: is this the same person? A face similarity test answers it with a number — but the number is only useful if you know what it measures.
What the score actually measures
A facial comparison tool does not “recognise” anyone. It maps each face into a list of measurements — the geometry between eyes, nose, mouth, jaw and so on — and then compares the two lists. The score is how close those two sets of measurements are.
That has an important consequence: the score describes the photos, not the people. Two pictures of the same person taken ten years apart in different lighting can score lower than two pictures of different people photographed the same way.
How to match two faces
Open the face comparison tool, add one photo to each side, and press compare. It runs in your browser — the pictures are not uploaded anywhere — and it is free with no account.
For a result you can trust:
- Use front-facing photos where the whole face is visible.
- Avoid sunglasses, masks, heavy beauty filters and extreme angles.
- Crop group shots so the face you care about fills a decent part of the frame.
- If you have several photos of each person, compare a few pairs rather than betting on one.
Reading the number
- High score. The two faces measure very alike. With good photos on both sides this is strong evidence of the same person.
- Middle score. Genuinely ambiguous. This is where photo quality, age gap or angle usually explains the result, and where you should compare more pairs rather than decide.
- Low score. The faces measure differently. With two clear, front-facing photos, that is good evidence of different people.
Notice that none of those say “match” or “no match” outright. Any tool that gives you a flat yes or no from two photos is hiding the uncertainty rather than removing it.
What quietly moves the score
- Age gap. Faces change most in childhood and after middle age. A decade between photos reliably drags the score down.
- Angle. A profile shot against a front-facing shot gives the tool much less to measure.
- Filters and retouching. Beauty filters reshape exactly the features being measured. They are the single most common reason two photos of one person score low.
- Resolution. A tiny or blurry face means fewer usable measurements.
- Family resemblance. Siblings, parents and children can score surprisingly high. If relatives are plausible, the score alone will not settle it.
Comparison or search: which do you need?
They answer different questions, and people often reach for the wrong one.
- Face comparison takes two photos you already have and tells you how alike the faces are. Use it when someone sends you a “proof” selfie, or when you want to know whether an old photo and a new profile show the same person.
- Face search takes one photo and looks for that face across public web pages. Use it when you have one picture and no idea who is behind it.
A common pairing: run a search on a profile photo to see where else it lives, then run a comparison between the profile photo and any “verification” selfie you were sent.
What a score cannot do
It cannot identify a stranger, it is not admissible proof, and it must not be used for decisions about employment, credit, housing or insurance. It is a way to get a sanity check before you trust someone online — nothing more, and used that way it is genuinely useful.
