Start with what the photo cannot tell you
A photo shows a face. It does not show who is typing. Even a genuine, unedited picture can belong to somebody other than the person who sent it, which is how most catfishing works: real photos, borrowed.
Check where else the picture appears
Search the image on the web. A picture that turns up under several names, on stock sites or on a model’s public page was probably not taken by the person you are talking to. No results is not proof of anything; most private photos are not indexed.
Look for a mark you can check, not one you can see
A badge, a tick or a watermark on an image is just more pixels. Anyone can add one. What matters is whether the mark leads somewhere you can check for yourself. A verified photo from Realr carries a short code and a QR. Open realr.me/p followed by the code and you see Realr’s own record of that photo.
Compare the picture, not just the code
A real code can be copied onto a different picture. On the photo’s Realr page you can upload the picture you were sent and have it compared with the one on record. If it is a different picture, the page says so.
Ask for one that was verified
If the photo has no mark at all, ask: “Could you send me a verified photo, or your Realr?” Someone who is who they say they are can do that in a minute. Notice how they respond, and treat pressure or excuses as information.
What a verified photo still does not prove
It proves the photo is genuinely of the person behind that Realr. It does not prove the person messaging you is them, and it says nothing about their intentions. Use it as one check among several.