RokRage Excel Viewer

Preview Excel .xlsx workbooks and .csv files directly in VS Code or VSCodium.

RokRage Excel Viewer is a local, read-only spreadsheet viewer. It does not upload your files or modify the source workbook.

Features

Display formatted values, formulas, fonts, colours, fills, borders, alignment and wrapped text.
Preserve merged cells, row heights, column widths, hidden rows and hidden columns.
Keep frozen rows and columns visible while scrolling.
Navigate worksheets with colour-accented Excel-style tabs.
Filter AutoFilter columns using interactive dropdowns.
Search the whole sheet or a selected column, with match counts, highlighting and result navigation.
Show only matching rows without changing the workbook.
Page through large result sets with first, previous, next and last controls or direct page entry.
Scroll large worksheets smoothly using virtualised row rendering.
Display formula results, with the formula available on hover.
Show hyperlinks and cell-note indicators.
Reload automatically when the source file changes.
Open CSV files with automatic comma, semicolon, tab and pipe delimiter detection.
Decode UTF-8, Windows-1252 and UTF-16 CSV files, including quoted fields and embedded newlines.
Export the current visible rows as CSV, JSON or InterSystems Health Connect lookup XML.

Rows are loaded into the preview on demand, so large worksheets can be scrolled without creating hundreds of thousands of browser elements. Extremely wide worksheets are limited to 250 columns and display a notice when truncated.

Getting started

Install RokRage Excel Viewer.
Open an .xlsx or .csv file from the Explorer.
If another editor is selected, right-click the file and choose Open With..., then select RokRage Excel Viewer.

Privacy

Workbook and CSV parsing takes place locally. The extension does not upload file contents. It opens spreadsheets in a read-only editor and never writes changes back to the source file.

Exports create a separate file only when you explicitly request one.

Exporting data

Export rows creates CSV, JSON or InterSystems Health Connect lookup XML from the current visible row set. CSV and JSON exports include a multi-select column picker.

Health Connect export asks for the lookup table name, key column and value column, then creates the IRIS version="26" .LUT import format. Blank keys, blank values, duplicate keys and invalid table names are rejected. Exports respect worksheet filters and the optional Only matching rows view.

Supported formats

Excel .xlsx workbooks.
Delimited-text .csv files.

Limitations

The extension does not edit workbooks. Preview filters do not modify the source file. Filter dropdowns display up to 1,000 distinct values per column, and worksheets are limited to 250 displayed columns.

Charts, embedded images, conditional formatting, macros, pivot tables and Excel theme colour transformations are not currently rendered. CSV values remain text so identifiers with leading zeroes are preserved.

When ExcelJS cannot read a valid workbook because its SpreadsheetML tags use explicit namespace prefixes, the viewer normalises a temporary in-memory copy. The original file is never changed.

Requirements

VS Code or VSCodium 1.90.0 or later.