Why your selfie is reversed

A front camera points at you, so the picture it forms is the picture somebody standing opposite you would see. That is not the picture you know. Every rehearsal you have ever done of your own expression happened in a mirror, which reverses left and right, so the face you are fluent in is a reflection of your actual face.

Phone makers resolved this the obvious way: the preview is mirrored so that moving your hand to the right moves it to the right on screen. Without that, framing a selfie would feel like operating a machine through a periscope. The mirroring is a usability decision about the live view and nothing more.

What gets written to storage depends on the phone, the operating system version and a setting that has been renamed several times. Broadly there are three behaviours. Some devices save the unmirrored picture — what the lens saw, and what other people see. Some save the mirrored preview, so the file matches what you were looking at while you took it. Some offer a switch, usually called something like mirror front camera or save mirrored photos, and default it to off.

This is why a selfie can look subtly wrong the moment you open it in the gallery. Nothing has gone wrong. You framed a mirror and were handed a photograph, and your own face is the one subject in the world where you can reliably tell the difference. Text in the background gives it away instantly: a shirt logo or a road sign that reads correctly to you in the preview will be backwards in the saved file, or the other way round.

The unmirrored file is a correct record of the scene and the mirrored one is not. Any lettering visible in the frame settles it: if the writing reads normally, the picture is the way a bystander saw it. If it reads backwards, the file carries the preview mirroring and every asymmetric detail in it is on the wrong side.

For a portrait that is going anywhere public, the unmirrored version is the one to use. For a picture that only you will look at, the mirrored version will simply feel more like you, and that is a perfectly good reason to keep it. What matters is knowing which one you have, rather than discovering later that a photograph you have been using is a reflection of the scene it claims to record.

A reflection is its own inverse. Reversing a mirrored selfie on the horizontal axis returns exactly the grid the sensor produced, with no quality cost from the transform itself — only the cost of writing the JPEG back out, which is avoidable by saving to PNG. The tool on the front page of this site does that in one keystroke, and the divider is there so you can look at both and decide which one is the face you meant.

One warning worth stating plainly: a video call is mirrored for you and unmirrored for everyone else, and no amount of adjustment on your side changes what they see. The reversal that bothers people in recordings of themselves is not a fault in the file. It is the first honest look most of us get at our own asymmetry.