Rotate vs Flip vs Mirror: What's the Difference (and Which Do You Need)?
These three get used interchangeably in everyday speech, but only two operations actually exist, rotating and flipping, and "mirror" is just the common name for one specific kind of flip. Picking the wrong one produces an image that's technically "turned around" but not in the way you meant.
Rotate
Turns the whole image around its center point, typically in 90 degree steps: 90, 180, or 270 degrees. This is what fixes a sideways phone photo (the camera was held on its side when the shot was taken) or an upside-down scan. A 90 or 270 degree rotation also swaps the image's width and height; 180 does not.
Flip, and why "mirror" means one specific flip
Flipping reflects the image across an axis instead of turning it, the dimensions stay the same either way. A horizontal flip, left and right swap, is what people mean when they say "mirror," because it's the same transformation a bathroom mirror applies to your reflection. A vertical flip (top and bottom swap) is the less common one, mostly used to fix an image that was captured upside-down by a sensor rather than a camera orientation issue. If text or writing in a photo reads backwards, that's a horizontal flip problem, not a rotation problem, no amount of rotating fixes mirrored text, since rotation never reflects anything.
Why some tools say "transpose"
"Transpose" is image-processing shorthand for a rotate-plus-flip combination applied together as one step, and it's also the exact term used inside a photo's EXIF orientation metadata to describe how a camera was physically held when it captured a frame. That's the real reason phone photos sometimes load rotated wrong in the first place: the sensor always captures the same physical orientation, and the phone records which way it was actually held as an EXIF tag, expecting the viewer to read that tag and rotate the display accordingly. A viewer that ignores the tag shows the raw sensor orientation instead, which is why the same file can look correctly oriented in one app and sideways in another.
Matching the problem to the fix
- Sideways photo → rotate 90° (clockwise or counterclockwise, whichever straightens it).
- Selfie or screenshot where text reads backwards → horizontal flip.
- Upside-down scan → rotate 180°.
- Image looks fine but a specific app displays it sideways → an EXIF orientation tag mismatch, not something rotating the pixels fixes; strip and bake the orientation in instead.
Doing it
Rotate and Flip an Image handles both operations, and lets you combine them (rotation applied first, then the flip), entirely in your browser. If the problem is specifically an EXIF orientation mismatch rather than needing the pixels themselves turned, see EXIF Viewer to check what orientation tag the file actually carries first.