Spreadsheet Viewer by Samuel Urias

View, search, sort, filter, and edit CSV, TSV, TAB, XLSX, and ODS files without leaving VS Code. Spreadsheet Viewer keeps the values stored in your files visible and lets you save changes back to the original document. XLSM workbooks open read-only.

Language: The extension's interface is currently in Spanish. This Marketplace page is in English. English interface translations are planned for a future release.

Highlights

• One table for common spreadsheet files: open CSV, TSV, TAB, XLSX, XLSM, and ODS files in an editor tab. XLSM workbooks are read-only.
• Edit and save cells: edit values in place or in the cell editor and save changes to the original file.
• Fill relative formulas: copy normal XLSX formulas down or right with adjusted A1 references, review the generated formulas, and apply or undo the full range as one operation.
• Create native XLSX tables: turn a safe rectangular range into a named Excel table with filters and a built-in style; the operation preserves cell values and can be undone.
• Manage simple XLSX sheets: add, rename, or delete sheets in reference-free workbooks, with undo and validation before changing the package.
• Move cell ranges safely: mark a range and move it to a selected cell in the same sheet after a confirmation. External clipboard pastes remain copies; formulas, merged cells, protected sheets, and sorted or filtered views are excluded.
• Format simple XLSX ranges: toggle bold, italic, text wrapping, alignment, or common number formats; merge empty cells and save frozen panes to the workbook. Each operation can be undone.
• Manage CSV records: insert or append an empty row, or delete selected rows with confirmation. These actions can be undone and are configurable in Settings.
• Fill selected ranges: repeat a value pattern or extend an explicitly chosen numeric series, review a preview, and undo the single resulting operation. Formulas and filtered/sorted views are excluded.
• Choose when changes are written: automatic saving after confirming an edit is on by default; it can be disabled to save with Ctrl+S (Cmd+S on macOS).
• Keep raw values visible: values are not silently converted to dates, percentages, or display-formatted numbers.
• Find data quickly: search the active sheet and jump to a cell by reference, such as B54.
• Sort and filter the view: sort by multiple columns and filter by raw values or conditions. These operations do not reorder or remove data in the file.
• Navigate with the keyboard: move through cells, select ranges, and begin editing by typing or pressing F2.
• Copy selected cells: copy raw TSV values, the current displayed values, or column labels with the selection. Filtered and sorted rows are copied in their visible order.
• Adjust the table layout: resize columns and rows, auto-fit columns, wrap text, and freeze visible rows or columns.
• Remember your view: restore selection, scroll position, search, sort, filters, and sizes per file and sheet. This can be disabled in Settings.
• Preview without editing: inspect a file from disk, preview unsaved CSV/TSV/TAB text, or explicitly preview another text file as CSV.
• Preview piped CSV input: optionally open VS Code's code - standard-input buffer as a read-only table; this is off by default.
• Inspect and edit XLSX formulas: supported formulas are calculated in a local Web Worker so they do not run on the grid's UI thread. Select a formula cell to edit its expression, or enable Editar como fórmula to create one. Syntax is checked before applying; tested function completions and explicit cell-reference insertion are available by default. Valid functions the calculator does not support can still be saved and are labeled unsupported in the cell details. Shared and array formulas cannot be edited. Calculated results are for display and are never written to the workbook.

Get started

1. Use VS Code 1.140 or newer and install Spreadsheet Viewer by Samuel Urias from the Extensions view.
2. In the Explorer, right-click a CSV, TSV, TAB, XLSX, XLSM, or ODS file.
3. Choose Abrir en Spreadsheet Viewer (Open in Spreadsheet Viewer).

You can also use the editor title button or run Spreadsheet Viewer: Abrir en Spreadsheet Viewer from the Command Palette. The default shortcut is Ctrl+Alt+Shift+O (Cmd+Alt+Shift+O on macOS).

Spreadsheet Viewer is an optional editor for these formats. To make it the default for an editable file type, use Open With… in VS Code and select the extension.

Files opened through a VS Code file-system provider are editable only when that provider reports write support for its URI scheme. Unknown or read-only schemes open as read-only; saves also recheck provider capability and preserve the in-memory draft if writing is unavailable.

The extension declares support for VS Code Restricted Mode. It reads spreadsheet contents as data and does not execute macros or workspace-provided code. A dedicated Extension Host test opens a CSV in an untrusted workspace and checks that its bytes remain unchanged.

Work with data

Sort and filter

Click a column heading to sort ascending, descending, and then clear that sort. Click another heading to replace the sort; use Shift + click to add a sort column. The numbered indicators show sort priority. T and N indicate text and numeric comparison. Use Alt + click to switch comparison mode, or Ctrl + click (Cmd + click on macOS) to remove one sort criterion. Limpiar orden (Clear Sort) removes every active sort criterion.

Use the filter button beside a heading to select raw values or enter up to two conditions joined with AND or OR. Filters on separate columns are combined with AND. The values list can be searched and paged; Apply, Cancel, and Clear control the filter. Active filters appear as removable chips above the table.

Sorting and filtering only change the visible projection. The source rows and the saved file remain in their original order. Search covers visible rows by default; choose Toda la hoja (Entire Sheet) to include filtered rows. If a match or cell reference is hidden, the view can reveal it by clearing the active filters.

Navigate and edit

• Click and drag to select a range. Shift + click or Shift + arrow extends the selection.
• Use arrow keys, Home, End, PageUp, PageDown, Tab, and Enter to move around the table.
• Press F2 or start typing to edit the selected cell. Press Enter or Tab to confirm; press Escape to cancel.
• Use the cell reference field to jump to a location such as B54.
• Use the search field and its previous/next controls to move through matches in the active sheet.

Range selection follows the visible order and skips filtered-out rows. Press Ctrl+C (Cmd+C on macOS) while the grid has focus to copy raw values. The Copiar mostrado and Copiar con encabezados buttons provide the other variants. TSV quoting preserves tabs, line breaks, quotes, Unicode, and empty cells. Paste TSV into the focused grid to apply the whole range as one undoable edit; a single value fills the selected range. Press Delete or Backspace to clear selected contents. Paste and clear are disabled for sorted, filtered, or searched views to prevent changes landing on unexpected rows. Formulas and unsupported cells are rejected by the edit preflight.

To move plain values within a sheet, choose Cortar rango and then Pegar movimiento at the destination. The move requires an unfiltered, unsorted, unsearched view and is confirmed as one undoable operation. Formula cells, merged cells, protected sheets, and unsupported workbook structures are rejected. Copying to an external clipboard or pasting external text never deletes the source.

For editable CSV files, Insertar fila adds an empty row below the selection, Añadir fila adds one at the end, and Eliminar fila(s) removes the selected range after confirmation. If the CSV has no rows or columns, Añadir fila asks how many fields the first record should contain. The actions are disabled while sorting, filtering, or searching; their visibility is controlled by spreadsheet-viewer.csv.showRowActions.

Adjust the view

Drag the dividers in the column and row headings to resize them. Autoajustar (Auto Fit) can fit the first column or all columns to their headings and a deterministic sample of up to 200 visible rows. Its tooltip explains the selected scope and sample-based sizing. The width is bounded to keep the table usable. Turn on Ajustar texto (Wrap Text) to wrap cell contents and grow visible rows automatically; manual row heights are retained while wrapping is active.

Set Filas fijas (Frozen Rows) and Columnas fijas (Frozen Columns) to keep the first visible rows or columns in place while scrolling. These layout choices affect the view only and are remembered per sheet.

Previews

The Command Palette includes these read-only options:

• Vista previa de hoja (Preview Sheet) reads the file from disk.
• Vista previa del buffer CSV/TSV/TAB (Preview Text Buffer) follows unsaved text changes in the active text editor.
• Vista previa como CSV… (Preview as CSV…) explicitly interprets a text file as CSV.

To automatically preview text piped into VS Code with code -, enable spreadsheet-viewer.stdin.openStdin. The setting only recognizes VS Code's temporary stdin file and opens it read-only. Plain Text and supported CSV language modes can provide the delimiter (including semicolon and pipe modes); .tsv and .tab always use tabs. No Rainbow CSV installation is required.

Opening the editable view while the text buffer has unsaved changes asks whether to save, discard, or cancel first.

Raw values and file compatibility

• CSV values remain text. The editor supports UTF-8 and UTF-16 files with a byte-order mark and detects comma, semicolon, or tab separators. .tsv and .tab files use tabs.
• XLSX and ODS values are read from their stored XML values. For example, a date-formatted XLSX number is shown as its stored serial value, not converted to a formatted date.
• XLSM opens in read-only mode. VBA macros and workbook code are never executed; formulas show their stored expression and cached value without recalculation. The package is never rewritten, preserving its macros and signatures.
• XLSX formula expressions and cached values remain distinct. Formula calculation is for display only and does not replace the original formula or cache. Unsupported formulas show their stored cache and are identified as unsupported.
• ODS formulas are shown with their stored cached value and are not recalculated.
• XLSX opens in raw-value mode. Ver libro optionally applies supported Excel number formats (including percentages and dates) to the grid; editing and saving keep the original raw values. Values with more than 15 significant digits and formulas remain raw. This is a presentation feature, not full Excel formatting support.
• The first CSV row can be displayed as a column heading; optional header capitalization changes only the visual label. CSV comment records can be hidden from the table while remaining in the file.
• CSV, XLSX, and ODS files are limited to 10 MiB. XLSX/ODS archives also have limits for expanded size, number of parts, sheets, rows, columns, and populated cells. Files over a limit are rejected as a whole rather than shown as a partial editable table.

XLSX and ODS support focuses on tabular data. Editing actions use narrower profiles than viewing; a workbook that opens successfully may still be rejected by a particular action. The host rechecks each operation and reports why it is unavailable. Current limits include:

These are tested conservative boundaries, not a guarantee of complete Excel or ODF round-trip fidelity. Validate important workbooks on copies in Excel or LibreOffice before relying on saved results. New support must name the package parts, relationships, and references it updates, include a writer and reference transformation where needed, and be checked against an independent application or fixture oracle.

Workbook sheets can be switched with scrollable tabs or the sheet selector. Hidden and very hidden sheets are labeled explicitly. Imported row/column dimensions and XLSX frozen panes are used for the grid. Basic XLSX bold, italic, alignment, wrapping, borders, and direct RGB font/fill colors are rendered; theme/indexed colors and advanced conditional or rich-text styles are not. Merged cells render when their rows remain in source order and the merge does not cross a frozen pane. When sorting or filtering changes row positions, the grid temporarily uses tabular cells and explains why. Selecting a covered cell moves to its merge anchor. Cell notes and links appear as text and are never opened automatically.

The XLSX editor can insert or delete selected rows and columns in a conservative workbook profile. It blocks structural edits when formulas, external references, merges, filters, protection, or workbook parts that it cannot update are present. Estructura XLSX can be hidden with spreadsheet-viewer.xlsx.showStructureActions. Formula editing is available by default and can be disabled with spreadsheet-viewer.xlsx.allowFormulaEditing.

Settings

All settings default to the values shown below. Add only the settings you want to override to User or Workspace settings.json.

For complete behavior details and examples, see the CONFIGURATION.md file included with the extension. Restablecer vista clears view preferences such as search, sort, filters, selection, and sizes. It does not change the document or discard an edit draft. Both view buttons include tooltips.

Development checks

The extension targets VS Code 1.140 or newer. Use Node.js 22 or newer for the development test tools; the VS Code test runner's dependencies use JavaScript syntax that older Node releases cannot parse. The project provides focused local tests and npm test for Extension Host coverage. Some host tests need a local VS Code installation or network access to download the configured test host. The latest full suite recorded in planning.md passed 113 tests with 1 pending. Some visual, remote-host, accessibility, and external Excel/LibreOffice checks remain open and are tracked there.

Language and support

The current interface is Spanish-only. English UI localization is planned but is not part of this release.

This is a personal project provided as is, without a promise of support, maintenance, or compatibility with every spreadsheet. Keep backups of important files and validate important workbooks on copies before relying on saved results.

License

Spreadsheet Viewer is licensed under the MIT License (see LICENSE). Bundled dependencies retain their own licenses; see THIRD-PARTY-NOTICES.md and the included license texts.