1Upload the PNG images that came out the wrong way round.
2Pick a quarter turn or a half turn, or type an arbitrary angle and choose a colour for the corners it will expose.
3Apply the rotation; the pixels and the orientation flag are reconciled so every viewer agrees on which way is up.
4Download the rotated PNG file.
Rotate PNG FAQ
How does Rotate PNG turn the file?
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Concretely, the pixel array is transposed and written back exactly, so a rotation of a lossless image is free in fidelity terms at any right angle and costs only resampling at an arbitrary one. Quarter turns and half turns are the common case and take the cheapest path available for the format.
Can I rotate by an arbitrary angle, not just 90 degrees?
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Yes, though the two are different operations underneath. A multiple of 90 degrees rearranges existing data; any other angle has to rebuild the grid and fill the corners, so it costs a resample and usually wants a background colour choosing.
Does the format decide whether rotation is lossless?
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It does. PNG is lossless DEFLATE with a full 8-bit alpha channel and optional 16-bit depth, so it never degrades on re-save but gets large on photographic content. That property is exactly what determines whether a quarter turn is free or costs a re-encode.
Anything specific to PNG I should know?
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Yes — there is no quality slider to get wrong — a PNG round-trips bit-exactly, so the only thing edits cost you is file size. It is the kind of thing that explains why a file looks right in one application and wrong in another.
Why does my file look correct on my phone but sideways elsewhere?
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Because the orientation is stored as an EXIF flag rather than in the pixels, and not every viewer honours it. Rotating here normalises the two — the pixels and the flag end up agreeing, so the file looks the same everywhere.
Can I rotate a whole batch in one go?
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Yes. The same rotation is applied across every file you upload, which is the practical fix for a folder of scans or camera output that all came in the wrong way round.
What can I upload to Rotate PNG?
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PNG, BMP and TIFF are the lossless raster formats this handles directly, and lossy sources (JPG, WebP, GIF) work too if you want them in the same batch. Multi-page TIFFs are detected and handled page by page.
Is there a file size limit on Rotate PNG?
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Yes: free accounts process images up to 25 MB each; lossless sources hit that ceiling sooner than photographs do, because nothing has been thrown away yet. If you are over it, converting to PNG first is often enough on its own — a BMP is routinely ten to twenty times the size of the identical image as PNG.
Will Rotate PNG lower the quality of my PNG images?
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No. A lossless source round-trips bit-exactly, so unless you explicitly ask for a lossy output format the pixels that come back are the pixels that went in. That is the whole reason to keep working in this family while you are still editing.
Can I run Rotate PNG on several PNG images at once?
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Yes — upload the set and they process in parallel under one set of settings. Lossless files are larger, so a big batch is bound by your upload speed rather than by the processing itself.
Does the alpha channel survive?
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Yes. PNG and TIFF carry a full 8-bit alpha channel and it is preserved end to end. It is only flattened if you deliberately target a format that has no alpha, in which case transparent pixels are composited onto white.
Does Rotate PNG cost anything?
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No. Rotate PNG runs free without an account and adds no watermark. Files are removed from the workers shortly after you download, and nothing about the image is retained.
