CHM 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 CHM format, this page is the shortcut: CHM is Microsoft's compiled help format: HTML topics, images and an index compressed into one legacy-but-everywhere file. Old software manuals, ebooks and documentation still ship as CHM.
iLoveConverter processes everything locally on your computer, which makes it private and fast: no upload wait, no server storage, no limits. Add as many files as you like — batch conversion is built in.
How CHM compares to 7Z
| CHM | 7Z | |
|---|---|---|
| Compression | LZX | LZMA / LZMA2 |
| Encryption | None | AES-256 native |
| Bundling | HTML topics + index in one file | Multi-file, solid mode |
| Best for | Legacy software manuals | Maximum compression, secure archives |
How to convert CHM to 7Z
- 1
Select your files
Drag & drop your CHM files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to 7Z". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted 7Z file individually, or grab everything at once as a ZIP archive.
About the CHM format
CHM (Compiled HTML Help) is Microsoft's format for bundling HTML topics, images and a searchable index into one file. An entire generation of software manuals, programming references and even novels shipped as CHM — and modern Windows no longer renders it comfortably.
Extracting a CHM gives you back the raw HTML topics and images: open them in any browser, convert them onward to PDF or EPUB, or migrate the content into a modern documentation system. The help tree becomes regular files.
+ Strengths
- ✓Unlocks decades of locked-in documentation
- ✓Topics come out as clean, standalone HTML
- ✓No deprecated viewer required
! Limitations
- −Index and search metadata do not convert
- −Topic filenames are often opaque codes
- −Some CHM files use encodings that need care
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 CHM to 7Z?
There is a concrete reason this conversion exists: Index and search metadata do not convert 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 CHM 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.
Is there a file size limit for CHM to 7Z?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.
Are the files inside my CHM archive modified?
No. Contents are unpacked in memory and repacked into 7Z byte-for-byte — the conversion changes the container, never the files inside it.
Is there a size limit for archive conversion?
There is no upload cap because nothing is uploaded — the practical limit is your device memory. A few hundred megabytes of unpacked content works comfortably on a modern computer.