QOI to 7Z Converter
Processing entirely on your device — large files may take a moment.
7Z is ideal for big archives you store or share with power users; convert to ZIP when the recipient just needs to double-click. If your files are still in QOI format, this page is the shortcut: QOI (Quite OK Image) is a 2022 lossless format with a ~200-line spec — PNG-class simplicity that compresses similarly fast.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How QOI compares to 7Z
| QOI | 7Z | |
|---|---|---|
| Compression | Lossless (RLE/delta) | LZMA / LZMA2 |
| Best for | Hobby engines, lossless simplicity | Maximum compression, secure archives |
How to convert QOI to 7Z
- 1
Select your files
Select your QOI file — it never leaves your device.
- 2
Convert instantly
The engine packs the file, byte for byte, into a 7Z container — no re-encoding, no quality change.
- 3
Download results
Download the finished 7Z archive.
About the QOI format
QOI (Quite OK Image, 2021) is a lossless format defined in one short specification document: a stream of simple run-length and delta ops over linear pixels. An encoder fits in 300 lines, decodes faster than PNG, and compresses comparably for photographic content.
It has found a home in emulators, demoscene projects and hobby engines — anywhere people want images without a codec dependency. Viewers rarely support it, so converting QOI to PNG is the way to bring these files into normal tools.
+Strengths
- ✓Radically simple spec (~200 lines)
- ✓Lossless with fast decode
- ✓No patent or licensing questions
!Limitations
- −Almost no viewer support
- −Larger than modern codecs for many images
About the 7Z format
7Z is the native format of Igor Pavlov's 7-Zip (1999), built around LZMA/LZMA2 compression — for years the ratio king against ZIP and RAR — with AES-256 encryption, solid archiving (similar files compress as one stream) and open, unpatented specifications. A 7Z of the same photos or code is routinely 20–40% smaller than its ZIP.
The trade-off is platform defaults: Windows Explorer and macOS Archive Utility do not open 7Z without third-party tools (7-Zip, PeaZip, Keka). It is the format for maximizing compression on your own terms, and for encrypted archives done properly (header encryption included).
+Strengths
- ✓Top-tier compression ratio (LZMA2)
- ✓Real AES-256 encryption, optional header encryption
- ✓Open format, free tooling everywhere
!Limitations
- −No native OS support — recipients need tools
- −Solid mode makes single-file extraction costly
Why convert QOI to 7Z?
There is a concrete reason this conversion exists: Almost no viewer support 7Z sidesteps that — Top-tier compression ratio (LZMA2) If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this QOI to 7Z converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Will I lose quality converting QOI to 7Z?
No — 7Z is a lossless format, so every pixel of the converted image matches your original QOI file. You can also adjust the quality/size balance before converting when the target format supports compression.
What happens to EXIF data and other metadata?
Conversions here re-encode the image, and re-encoding generally does not carry the original metadata over. If the EXIF data of your QOI files matters (camera model, GPS, timestamps), keep the original file as the master and treat the converted copy as the shareable version.
Will transparent areas survive the conversion to 7Z?
Transparency is kept whenever 7Z actually supports an alpha channel. If the target format has none (like JPG), transparent areas are flattened onto a white background — that is a property of the format, not of this tool.