Rotate Image

Two different jobs, and they want opposite things

Worth separating before you start, because it decides which settings you want.

Turning a sideways photo upright is a quarter turn — 90 degrees left or right, or 180 for an upside-down one. The image stays rectangular, nothing is added and nothing is lost. Use the quick buttons and you are done.

Straightening a crooked one is a small angle: a tilted horizon, a scan that went through the feeder skewed, a photo of a document taken at three degrees off. Drag the slider a couple of degrees and watch the preview.

And here is the thing nobody explains: a rotation that is not a multiple of 90 degrees always leaves empty triangles at the corners. That is geometry, not a flaw — a tilted rectangle cannot fill an upright one. Every tool has to do something about those triangles, and there are only two options:

Fill them, which is what this tool does. The canvas grows so the whole image still fits, and the corners get the background colour you pick. You keep every pixel of the original.

Crop into the picture until the empty corners are cut away, which is what tools called "straighteners" quietly do. You get a clean rectangle and you lose a border all the way round — a few per cent of the image, more at steeper angles.

Neither is wrong. Fill is right for a scan or a document, where losing an edge might cost you text. Crop is right for a photograph, where a filled corner would look odd. If you want the cropped look, rotate here and then use Crop Image — that way you decide exactly what to lose instead of a tool deciding for you.

Choosing the background

This is the setting that determines whether a straightened image looks finished.

White is the default and the right answer for a scanned document, a receipt or a page of text, because the page is already white and the corners disappear into it.

Transparent is for a logo, an icon or anything you will place on top of another background. Choose it and the output automatically becomes a PNG, because transparency cannot exist in a JPEG — so you get real transparency instead of the black corners that catch people out elsewhere. The file will be larger than a JPEG.

Black suits a dark photograph, and a custom colour lets you sample the picture's own edge tone, which is the trick for making a small rotation invisible. Pick the colour of whatever sits at the borders — the wall, the sky, the desk — and the triangles stop reading as triangles.

For a quarter turn none of this matters, since there are no corners to fill.

What rotating costs the file

Three honest notes, because "rotate" sounds free and is not quite.

A JPEG is re-encoded. The rotated image is saved as a fresh JPEG at high quality, which means one generation of compression loss. Once is invisible. Rotating the same JPEG five times, saving each time, is not — so if you are experimenting, go back to your original rather than re-rotating the download.

An odd angle resamples the pixels. At an angle that is not a multiple of 90, every output pixel is interpolated from its neighbours, so fine detail and sharp text soften very slightly. It is the unavoidable cost of straightening and it is much smaller than the benefit. Quarter turns do not have this problem.

All metadata is stripped. EXIF data, GPS coordinates, camera and lens information, timestamps — none of it survives. That is a privacy gain if you are about to post the photo, since the location where it was taken goes with it, and a loss if you were relying on that data being there. Copy the original somewhere safe first if the camera information matters.

Why your photo looked sideways in the first place

This explains a genuinely confusing problem, and it is the best reason to use this tool.

When you take a photo on a phone held sideways, the camera does not rotate the picture. It stores it as-shot and adds a small note in the file saying "display this rotated 90 degrees". Good software reads the note. Older software, some upload forms and a lot of websites ignore it.

That is why the same photo can look upright in your gallery and sideways once you email it, put it in a document or upload it to a form — and why rotating it in your phone's photo app sometimes does not stick.

Rotating it here fixes it permanently, because the pixels themselves are turned and the note is discarded. There is nothing left to ignore. If a photo keeps appearing sideways somewhere despite looking fine to you, this is the fix.

It is also why Flip Image is the wrong tool for that job: flipping mirrors the image, so any text in it comes out backwards. Rotation turns it; flipping reverses it.

Everything stays on your device

The image is loaded and redrawn in your browser. Nothing is uploaded, there is no watermark, no account and no size limit beyond what your device can hold in memory. A PNG stays a PNG; anything else comes back as a high-quality JPEG, unless you chose a transparent background, in which case it becomes a PNG.

Related tools

Crop Image is the natural next step if you want the corners cut away rather than filled. Flip Image mirrors instead of turning, which is a different operation and rarely the one you want for a sideways photo. Rotate PDF does the equivalent job on a PDF, and it is genuinely lossless there because a PDF can simply record the rotation rather than redrawing the page.