XLS to XZ Converter
Processing entirely on your device — large files may take a moment.
Excel 97-2003 Workbook and XZ Compressed File exist for different jobs: XLS is the classic Excel 97–2003 workbook format, still produced by many banks, ERP systems and export tools. Unpack XZ into ZIP/TAR for tools that cannot read LZMA2.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How to convert XLS to XZ
- 1
Select your files
Select your XLS file.
- 2
Convert instantly
The file bytes are gzip-compressed in place — the same archive your server or build tool produces, made locally.
- 3
Download results
Download the .gz file — ready to upload, serve or attach.
About the XLS format
XLS is the legacy Excel binary format (BIFF8, Excel 97–2003). It does everything its era supported — sheets, formulas, formatting, VBA macros — under hard limits: 65,536 rows and 256 columns per sheet. Millions of government, banking and manufacturing templates were built on it, which is why it still arrives in inboxes.
There is no reason to create new XLS files: XLSX handles everything better with no row ceiling. The realistic use case is reading — opening or converting historical files, or feeding systems whose import filters predate 2007.
+Strengths
- ✓The only format ancient Excel-era systems accept
- ✓Full BIFF8 feature set: formulas, macros, formatting
!Limitations
- −65,536-row and 256-column ceiling per sheet
- −Obsolete binary spec, awkward for modern tools
- −Macro-enabled files carry security risk
About the XZ format
XZ wraps the LZMA2 algorithm: the best ratio of the common Unix compressors, which is why distribution packages and source releases pick it when bandwidth matters more than CPU.
Windows Explorer and many cross-platform tools cannot open it — unpacking to ZIP or TAR makes the payload portable.
+Strengths
- ✓Highest common ratio
- ✓Standard for Linux packages
- ✓Integrity checks built in
!Limitations
- −Memory-hungry at high settings
- −Sparse support outside Linux
Why convert XLS to XZ?
Converting makes sense where the strengths of XZ meet what XLS cannot give you. Highest common ratio Meanwhile 65,536-row and 256-column ceiling per sheet One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this XLS to XZ 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.
What about special characters and non-English text?
Everything is handled as UTF-8. When you export CSV for Excel, a UTF-8 BOM is included automatically so Chinese, Japanese, Korean and accented characters display correctly on both Windows and macOS.
Are the files inside my XLS archive modified?
No. Contents are unpacked in memory and repacked into XZ byte-for-byte — the conversion changes the container, never the files inside it.
What about folders and directory structure?
The full directory tree is preserved: folders stay folders, and deep paths arrive exactly as they were packed in the XLS file.