XLSB to GZ Converter
Processing entirely on your device — large files may take a moment.
Excel Binary Workbook and Gzip Compressed File exist for different jobs: XLSB is Excel's binary workbook format: identical content model to XLSX, packed in a binary container that opens and calculates faster on huge sheets. Unpack a .gz into a normal file or repack it as ZIP/TAR when the receiving tool does not understand gzip.
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 to convert XLSB to GZ
- 1
Select your files
Select your XLSB 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 XLSB format
XLSB is Excel's binary workbook format: the same content model as XLSX but packed in a binary container instead of XML. It opens and calculates noticeably faster on huge sheets and produces smaller files — the tradeoff is that almost nothing outside Excel can read it, and macro-bearing workbooks cannot use it at all.
Because the cell data is identical to XLSX, converting XLSB to CSV, JSON or XLSX loses nothing: SheetJS parses the binary parts natively in your browser, and the output is an ordinary spreadsheet that every tool accepts. If you only need the values, CSV is the shortest path.
+Strengths
- ✓Faster open/calc and smaller files on huge sheets
- ✓Full fidelity to XLSX content model
- ✓Reads natively in-browser (SheetJS) — no upload
!Limitations
- −Opaque binary — no diffing or git-friendliness
- −Cannot hold VBA macros
- −Few third-party readers outside Excel/SheetJS
About the GZ format
A .gz file is one file squeezed by gzip — not an archive. kernel.org tarballs are “tar inside gz”, but plenty of logs, JSON dumps and CSV exports travel as plain .gz. Opening one means decompressing it back to the original bytes.
Repacking into ZIP or TAR gives the decompressed file a container that every GUI tool opens without a second thought.
+Strengths
- ✓Everywhere on Linux and macOS
- ✓Fast, well-understood compression
- ✓Streams natively from any tool
!Limitations
- −Single file only — no directory tree
- −No encryption or integrity metadata
Why convert XLSB to GZ?
Converting makes sense where the strengths of GZ meet what XLSB cannot give you. Everywhere on Linux and macOS Meanwhile Opaque binary — no diffing or git-friendliness One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this XLSB to GZ 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 XLSB to GZ?
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 XLSB archive modified?
No. Contents are unpacked in memory and repacked into GZ 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 XLSB file.