Flipping mirrors an image across an axis. Horizontal flipping swaps left and right, which is what you need for a selfie — front cameras record the scene mirrored, so text in the background comes out backwards and the composition reads the wrong way round. Vertical flipping swaps top and bottom, useful for correcting a scan fed in upside down or for building a reflection effect.
The operation is geometrically exact. Each pixel moves to a mirrored position with no interpolation, no averaging and no blurring — the only change to the data is the re-encoding step afterwards, done at JPEG quality 0.92.
The flip is a canvas operation running in your browser. Your photos are not uploaded to be processed.
-edited.The two are easy to confuse but produce different results. Rotating 180 degrees turns the image upside down and keeps the handedness — text is still readable if you stand on your head. Flipping vertically also puts the top at the bottom but mirrors it, so text becomes reversed.
The practical test: if letters in the picture read backwards afterwards, you flipped. If they read normally but upside down, you rotated. Use Rotate Image when the camera was held the wrong way; use Flip Image when the image itself is mirrored.
Phone front cameras show you a mirrored preview so that moving left moves your reflection left, which feels natural. Some phones save the mirrored version and some save the true one, and which you get varies by manufacturer and by app.
The giveaway is text: a logo on your shirt or a sign behind you will read backwards in a mirrored photo. Flip horizontally and it comes out right — though your face will look subtly unfamiliar to you, since you are used to seeing it in a mirror.
Rotating turns the image around its centre and preserves handedness. Flipping mirrors it, which reverses handedness — text reads backwards afterwards. If your photo is upside down, rotate; if it is mirrored, flip.
No, not geometrically. Pixels are mirrored to exact positions with no interpolation. The only change is the re-encoding, done at quality 0.92 for JPEG, which is visually lossless.
The front camera saved the mirrored preview rather than the true image. Flip it horizontally and the text reads correctly again.
Yes. Add the whole batch and the chosen flip is applied to every image, with results delivered as a ZIP.
No. JPG stays JPG and PNG stays PNG, with transparency preserved in PNG output.
No. The flip is a canvas transform performed entirely in your browser.