Rotate and Flip Image

How to rotate or flip an image

Rotate vs flip: what is the difference?

Rotating turns the image around its center point. 90° right takes a portrait image and makes it landscape. 180° flips it upside down. These are the most common fixes for photos taken in the wrong orientation by a camera that did not read the EXIF rotation data.

Flipping mirrors the image along an axis. Horizontal flip creates a mirror image — left becomes right. Vertical flip flips it top to bottom. Useful for creating symmetrical compositions, correcting selfie camera mirroring, or just making something look different without rotating it.

Both operations are lossless when done correctly. No quality is lost. The pixel data is rearranged, not re-compressed.

Why your photo looks sideways in one app and upright in another

This is the most common reason people reach for a rotate tool, and the photo is usually not rotated at all. Cameras and phones rarely turn the pixels when you hold the device sideways. They record the picture the way the sensor saw it and write a small note in the file called the EXIF Orientation tag, which tells software how to display it.

Software that reads the tag shows the photo the right way up. Software that ignores it shows the raw sensor data, which is rotated. That is why one file looks correct in your phone gallery and in a browser, then lands sideways in a document, an upload form or an older desktop program.

The tag has eight values covering rotation and mirroring:

Values 6 and 8 cause almost every real complaint, because those are what you get from holding a phone in portrait. When you rotate an image here the pixels themselves are turned and the result no longer depends on a tag, so every program agrees which way is up. That is a real fix rather than a workaround.

Is rotating lossless?

It depends on the format and on how the rotation is performed. Turning pixels by 90, 180 or 270 degrees is a lossless rearrangement in principle, because no pixel value has to change, they only move. PNG and WebP in lossless mode keep that promise exactly.

JPEG is the exception worth knowing. A JPEG stores the image in blocks, normally 8 by 8 pixels, grouped into larger units of 16 by 16 once the usual chroma subsampling is applied. A truly lossless JPEG rotation is only possible when the width and height divide cleanly into those units. When they do not, the edge blocks have to be rebuilt, and specialist tools either trim a few pixels or accept a small change at the border.

This tool avoids the problem by saving the rotated image as PNG, which is lossless, so the rotation adds no compression at all. The trade off is size: a PNG of a photograph is usually larger than the JPEG it came from. If that matters, run the result through the compress tool afterwards.

Rotate, flip and mirror are three different operations

Rotating turns the whole frame around its centre. A portrait picture becomes landscape and the dimensions swap, so 3000 by 4000 becomes 4000 by 3000.

Flipping horizontally mirrors left and right and the dimensions stay the same. This is the fix for a selfie that came out reversed, because most front cameras show a mirrored preview and some save it that way, which is why text in the background reads backwards.

Flipping vertically mirrors top and bottom. It is rarer, used for reflections or for a scan that was fed in the wrong way round.

One thing to watch: a horizontal flip is not the same as a 180 degree rotation. A 180 rotation is a horizontal flip and a vertical flip applied together. If you only need to undo mirroring, use flip, because rotating will also turn the picture upside down.

FAQ