Excel to CSV Converter
Convert Excel (.xlsx, .xls) files to CSV instantly - free, no upload, works entirely in your browser.
Drag files here or Tap to browse
Files are processed locally and never uploaded
Up to 500 MB Β· up to 50 files
Select Output Format
Upload a file to start converting
Quick Answer
Convert Excel (.xlsx, .xls) files to CSV instantly - free, no upload, works entirely in your browser. The conversion runs entirely in your browser - your file is never uploaded to a server.
How to Convert in 3 Easy Steps
Upload: Select or drag your Excel file
Convert: Click convert to start the CSV conversion
Download: Save your converted CSV file
Key Features
- Excel: Excel workbook (.xlsx or .xls)
- CSV: Comma-separated values text file
- All processing happens locally in your browser
- No registration or installation required
- Your files remain private - nothing is uploaded
Frequently Asked Questions
How do I convert EXCEL to CSV?
Upload your Excel file above and click convert. The CSV file is generated directly in your browser and downloaded automatically.
Is my data uploaded to a server?
No. Parsing and conversion happen locally in your browser using JavaScript - your spreadsheet data never leaves your device.
Is there a file size limit?
There is no hard limit, but very large files (100MB+) may be slow depending on your device memory.
Is this converter free?
Yes - completely free with no watermarks, sign-ups, or hidden limits.
How this conversion works
Conversions run inside your browser using WebAssembly. Files are decoded, transcoded, and re-encoded without being uploaded to any server. Open your browser DevTools Network tab while using this tool β no file upload request is made. The WASM build is cached on first visit so subsequent conversions start instantly.
What this tool canβt do
- Extremely large files are bounded by your device memory, not by server capacity. A very low-memory tablet may fail to load a 4K video where a desktop completes in seconds.
- WebAssembly codec support lags slightly behind native desktop tools. For obscure or experimental codecs, a native tool (like desktop FFmpeg) is still the right choice.
When to consult a professional
If you need batch-processing millions of files, a server-side pipeline will outperform per-user browser conversion. For DRM-protected media, a legitimate licensed reader is required.
Sources
- [1]MDN β WebAssembly (Wasm)DocumentationΒ·developer.mozilla.orgΒ·Accessed Apr 21, 2026
- [2]FBI Denver β Free Online File Converter Scam WarningOfficial sourceΒ·fbi.govΒ·Accessed Apr 21, 2026
Public service announcement on malicious online file converters.

Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).