QOI Converter
Convert any image to QOI in your browser. You get a lossless RGBA QOI file. QOI is best for fast lossless storage in games and tools. Batch convert any number of files; nothing is uploaded.
- Processed locally
- No upload, no wait
- No sign-up
- No watermark
Drop images here
or choose files · paste with Ctrl/⌘ V
JPG, PNG, WebP, HEIC, AVIF, GIF, TIFF, SVG, RAW, PSD, JXL, BMP, ICO and more
How to use Convert to QOI
- 1
Drop your images or click to choose them. You can also paste from the clipboard.
- 2
QOI is written losslessly, so there is no quality to set.
- 3
Click Convert. Each file is processed on your device in a background thread.
- 4
Download files one by one or all at once as a ZIP.
Why use Aback Images for convert to qoi
Processed on your device
Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.
Fast batch conversion
Several files are converted in parallel worker threads, with per-file progress and cancel.
Content-checked input
Files are identified by their bytes, not their name, so a mislabelled file still converts correctly.
Real control when you want it
Resize, rotate, background colour, metadata and codec options sit under More options.
About Convert to QOI
About QOI
QOI is a modern lossless format that encodes 20-50 times faster than PNG with similar file sizes. It is popular in games and tools that value speed and simplicity.
A QOI file is a 14-byte header ('qoif', width, height, channels, colour space), a stream of chunks that each encode a run, an index into 64 recently seen colours, a small difference from the previous pixel or a literal value, and an 8-byte end marker.
Strengths: Extremely fast lossless encode and decode; Simple, open spec.
Drawbacks: Not supported by browsers or mainstream apps.
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Frequently asked questions
Which apps open QOI files?
Game engines, GIMP 3, ImageMagick, XnView MP and many small libraries. It does not open in web browsers.
Which formats can I convert from?
Anything this site can read: JPG, PNG, WebP, AVIF, HEIC, GIF, SVG, TIFF, BMP, ICO, JPEG XL, PSD, RAW and more. Files are identified by their bytes, so a mislabelled file still converts.
Are my images uploaded anywhere?
No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.
Can I process many files at once?
Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.
Is it free? Is there a file limit or watermark?
It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.