How to use Image Rotator
- 1Drop in one image, or up to 50 as a batch
- 2Drag the dial to any angle, or pick a quarter turn
- 3For angles off the right angles, choose a background colour
- 4Check the preview — the canvas grows to hold the rotated image
- 5Download the result, or the batch as a ZIP
What Image Rotator does
Rotating by a multiple of 90 degrees is simple: the pixels move to new positions on a grid the same shape, or one turned on its side, and nothing is invented or lost. Every pixel that went in comes out.
Any other angle is a different operation. The rotated image no longer fits its original rectangle — a square turned 45 degrees needs a canvas about 40% wider in each direction — and the corners of that larger canvas contain nothing, so they have to be filled with something. Pixels also no longer land on grid positions, so each output pixel is interpolated from several input ones. That is why free rotation costs a little sharpness and right-angle rotation does not.
When to use it
- Straightening a crooked photo
- A handheld shot with a tilted horizon usually needs one or two degrees. The dial makes that adjustment directly rather than guessing at a slider.
- Fixing a sideways photo
- A picture taken with the phone turned, saved without its orientation flag honoured, needs a single quarter turn to be right.
- Correcting a scan
- Paper fed slightly askew produces a document tilted by a few degrees. Rotating back makes it read properly and look deliberate.
- Rotating a batch consistently
- A set of photos from the same camera orientation can all be turned the same way in one pass and downloaded together.
Image Rotator settings explained
- Angle dial
- Any angle, dragged directly. Small values are what you want for straightening — one or two degrees is usually enough to fix a tilted horizon, and more than five rarely looks like a correction.
- Quarter turns
- 90, 180 and 270 degrees. These are lossless in the sense that matters: no interpolation is needed, no canvas growth occurs, and no background is exposed.
- Background colour
- Fills the corners that a free rotation leaves empty. Only appears when the angle is not a multiple of 90, because right angles expose nothing.
- Automatic canvas growth
- The output canvas is enlarged to contain the whole rotated image rather than cropping it. A 45-degree rotation of a square needs roughly 40% more in each dimension.
Right angles compared with free rotation
| 90 / 180 / 270 | Any other angle | |
|---|---|---|
| Pixels interpolated | No | Yes |
| Canvas grows | No | Yes |
| Corners exposed | None | Filled with your colour |
| Sharpness | Unchanged | Very slightly softened |
Limits and what to expect
- Free rotation interpolates, which softens fine detail very slightly.
- The canvas grows for non-right angles, so the output has larger pixel dimensions than the input.
- Corners exposed by rotation are filled with a flat colour — nothing is reconstructed there.
- Saving to JPEG discards transparency, so the exposed corners become solid whatever you chose.
- 50 files per batch, 100 MB each, 300 MB per queue.
Troubleshooting
- The image has coloured triangles in the corners
- That is the background showing through where the rotated image does not reach. Set the colour to match where the image will sit, or crop the result to the largest rectangle that contains only image.
- The output is larger than the original
- The canvas has to grow to contain the rotated rectangle. A 45-degree rotation needs roughly 40% more in each dimension. Crop afterwards if you need the original dimensions back.
- The image looks very slightly softer
- Free rotation means output pixels no longer align with input pixels, so each is interpolated from several. The effect is small and unavoidable at any angle that is not a multiple of 90.
- My photo was already sideways before I rotated it
- Cameras record orientation as a metadata flag rather than turning the pixels, and some software ignores it. Rotating here writes the correction into the pixels themselves, so it holds everywhere.
Your files and your privacy
Rotation is performed on a canvas inside your browser tab using your own device. No image is uploaded, and batch ZIPs are built locally. The tool works with the network disconnected once the page has loaded.
What to use next
FAQ
Can I rotate an image by a few degrees?
Yes, the dial accepts any angle. One or two degrees is usually all a tilted horizon needs. Bear in mind that any angle other than a multiple of 90 enlarges the canvas and exposes corners that have to be filled.
Why did the image get bigger when I rotated it?
The rotated rectangle does not fit inside the original one, so the canvas is enlarged to contain it rather than cropping the corners off. At 45 degrees that is about 40% more in each direction.
Does rotating reduce quality?
At 90, 180 and 270 degrees, no — pixels simply move to new grid positions. At any other angle, output pixels fall between input pixels and have to be interpolated, which softens fine detail very slightly. It is not usually visible but it is real.
How do I get rid of the corners?
Either set the background colour to match wherever the image will be placed, or crop the result to the largest rectangle containing only image. There is nothing to reconstruct in those corners — they were never photographed.
Why is my photo sideways in some apps but not others?
Cameras store orientation as a metadata flag instead of rotating the pixels, and software disagrees about whether to honour it. Rotating here bakes the correction into the pixels, so every program shows it the same way.
Are my images uploaded?
No. Everything happens on a canvas in your browser, on your own device.