XLS Viewer

View .xls (Excel 97-2004) files directly in VS Code — with full fidelity to the original formatting.

Features

• 📊 View .xls files — double-click any legacy .xls file in VS Code's file explorer
• 🎨 Original formatting preserved — colors, fonts, bold, borders, alignment, merged cells
• 📐 Column widths & row heights — exactly as in the original file
• 🧊 Freeze pane — frozen rows/columns stay fixed while scrolling
• 👁️ Hidden rows/columns — respected from the original file
• 📑 Multiple sheets — dropdown + tabs to navigate
• 🔍 Read-only — the original file is NEVER modified. Safe for production data.
• 📄 Export to JSON / CSV — extract data for pipelines
• 📅 Readable dates — dates normalized to DD/MM/YYYY
• 🌙 Dark/Light theme — follows your VS Code theme
• ⚡ Fast — canvas-based rendering with virtual scrolling

Why XLS Viewer?

Legacy .xls files (Excel 97-2004 binary format) are still everywhere in enterprise and banking systems, but almost no VS Code extension handles them well. Most only support modern .xlsx, and the all-in-one office extensions treat .xls as an afterthought.

XLS Viewer is focused on exactly one job: viewing legacy .xls files with their formatting intact, safely and read-only.

Installation

VS Code Marketplace (recommended)

1. Open VS Code
2. Go to Extensions (Ctrl+Shift+X)
3. Search for "XLS Viewer"
4. Click Install

Or from the command palette (Ctrl+Shift+P):

ext install santyvv.xls-viewer

Open VSX (for Cursor, Windsurf, VSCodium, code-server, etc.)

Install from open-vsx.org:

ovsx install santyvv.xls-viewer

Manual (VSIX)

Download the .vsix from the GitHub Releases, then:

1. VS Code → Extensions → ... → Install from VSIX...
2. Select the downloaded file

Usage

1. Install the extension
2. Open any .xls file in VS Code
3. The spreadsheet opens in a visual editor tab with full formatting
4. Navigate sheets with the dropdown or tabs
5. Export to JSON/CSV if you need the data

Supported Formats

Requirements

• VS Code 1.80.0 or higher

Known Limitations

• Read-only: this extension is for consultation only. Editing is intentionally not supported — that's what makes it safe for production files.
• Formulas: shown as text (not calculated).
• Conditional formatting, charts, images: not supported by the rendering engine.

Release Notes

See CHANGELOG.md.

License

MIT © 2026 Santiago Valencia

Support

Report issues at: github.com/santyvv1993/xls-viewer/issues