Node.js
Read local files, uploads, S3/R2 objects, and other byte sources.
XLSB to Markdown in your browser.
Convert XLSB files to GitHub-Flavored Markdown directly in your browser.
Your XLSB stays on your device. No upload. No account.
- npm @mdgate/xlsx
- license MIT
- runtime Node.js · Edge · browser
Starting local converter
Use XLSB to Markdown in your app
$
npm install @mdgate/xlsx
import { toMarkdown } from '@mdgate/xlsx';
const markdown = await toMarkdown(bytes);Pure TypeScript, Node.js, Cloudflare Workers, Edge, Browser, No Python, No native addons, No WASM, Zero third-party runtime dependencies
How XLSB to Markdown works
- XLSB
- workbook parsing
- sheets · cells · tables
- GitHub-Flavored Markdown
Built for JavaScript runtimes
Cloudflare Workers
Parse Excel workbooks directly inside Workers without Excel or a native binary.
Browser
Convert XLSB locally without uploading it to a server.
Edge
Run the same TypeScript converter in compatible Edge runtimes.
What @mdgate/xlsx extracts
- One Markdown section per sheet
- GitHub-Flavored Markdown tables
- Merged cells
- Header-row detection
- Number formats (dates, percents, currency-style text)
- Shared strings and typed cell values
- Encrypted workbook detection
Why @mdgate/xlsx
Runs where your JavaScript runs
No separate processing service. The converter is TypeScript you can call from Node.js, Cloudflare Workers, Edge runtimes, and browsers.
Local conversion
XLSB files can stay inside your application or browser.
Content detection
Recognizes XLSB files from their contents, not only the filename.
Deterministic parsing
The same XLSB file produces repeatable Markdown without model inference.
Small runtime surface
No Python. No native addons. No WASM. No third-party runtime dependencies.
XLSB for AI agents
Turn XLSB files into content your agent can actually work with.
- XLSB
- Markdown
-
- grep
- search
- chunk
- index
- cache
- cite
- reason
Need more than XLSB?
One format
@mdgate/xlsx
Your own set
@mdgate/core
+ @mdgate/xlsx
+ @mdgate/pdf
+ @mdgate/docx
Broad file support
@mdgate/converters
FAQ
Can I convert XLSB to Markdown without uploading it?
Yes. XLSB files can be converted locally in the browser.
Does XLSB to Markdown work in Cloudflare Workers?
Yes. @mdgate/xlsx runs directly in Cloudflare Workers.
Does it require Python?
No.
Does it require native addons or WASM?
No.
What does it output?
GitHub-Flavored Markdown.
Can I install only the XLSB converter?
Yes. Install @mdgate/xlsx instead of the complete converter set.
Does this convert CSV?
No. Use @mdgate/csv for .csv and .tsv.