Turning and flipping without losing anything
A turn by 90 or 180 degrees, or a flip, only moves pixels. Nothing has to be calculated between two pixels, so nothing is blurred. A picture saved as PNG comes out identical to the original, pixel for pixel. The one caveat is see-through pixels: browsers store them with their colour already multiplied by their transparency, so a half-transparent pixel can change by a level or two, and a nearly invisible one by a few more, when it goes through this tool. Fully opaque pixels are exact.
The buttons add up. Rotate right followed by Rotate left puts the picture back, and two flips cancel each other. A flip and a turn together can give any of the eight possible orientations. The line under the buttons describes the current state in words, for example "Flipped left to right, then turned 90° left". Undo all turns returns to the original.
A flip is not a rotation. Rotating by 180 degrees turns the picture upside down: writing is upside down but not reversed. Flipping vertically mirrors it, like a reflection in water, and writing comes out reversed. Rotating by 180 degrees is the same as one flip in each direction. The flip image page goes into mirroring.
Straighten a crooked horizon
Move the slider, type an angle, or use the small buttons that change it by a tenth of a degree. A positive angle turns the picture clockwise. Switch on the grid on the preview and line it up with the horizon, a door frame or a building edge. Most crooked photos need a degree or two.
Turning a picture by a small angle leaves its corners empty, because a turned rectangle no longer fits in its old frame. You decide what happens to them:
- Crop them away (the default). The result is the largest rectangle with the same shape as the original that fits entirely inside the turned picture. A 4000 by 3000 photo turned by 3 degrees comes out at 3743 by 2807 pixels and keeps about 88 percent of the picture. At 1 degree it keeps about 96 percent, at 5 degrees about 81 percent.
- Fill with a colour. The picture grows to hold the turned one, and the corners are the colour you choose. The same photo turned by 3 degrees is 4152 by 3206 pixels.
- Transparent. The same size as the fill, with see-through corners. This needs PNG, WebP or AVIF, because JPG cannot be transparent. If a JPG is among the results, that JPG gets the background colour in its corners instead and the page says so, while the PNG, WebP and AVIF results keep see-through corners.
Turning by an angle that is not a multiple of 90 degrees has to calculate new pixels between old ones. The tool uses bicubic sampling over sixteen pixels, which keeps edges crisp and avoids the staircase look. Colours are weighed by transparency, so the edge of a cut-out does not pick up a dark rim, and the edge of the turned picture is smoothed over one pixel.
Sideways photos and rotation tags
Phones and cameras often store a photo in the shape of the sensor, sideways, together with a small note that says how to turn it. Some programs honour the note and others ignore it, which is why a photo can look right in one place and sideways in another. This tool applies the note when it opens a picture, so you see the photo the right way up, and saves the result upright with no rotation tag. It shows upright everywhere.
Metadata such as camera details, date and GPS location is removed by default. Choose Keep to copy the EXIF block from JPG, PNG and WebP originals. The rotation note in the copy is reset, so the picture is never turned twice.
Formats and honest notes
Rotating a JPG saves a new JPG, so the picture is compressed once more. At quality 95, the starting value here, the loss is very small and hard to see, but it is not zero. Some desktop programs can turn a JPG by 90 degrees without recompressing it, and this tool cannot. PNG is exact. WebP and AVIF are compressed like JPG, so keep a high quality if you will edit the picture again.
Pictures up to 100 megapixels are accepted. Turning by an angle with filled or transparent corners makes the picture a little larger, and a result above the limit gives a plain message. A batch is processed several pictures at a time, large ones one at a time, and Cancel leaves the finished files alone.