Open Madosuite
Alpha, the core workflow works end to end

Grid, a free spreadsheet in your browser

Spreadsheets with 500+ functions, dynamic arrays, pivot tables and charts, saved as .xlsx. A free alternative to Excel.

Open GridGrid vs Excel
Grid running in Madosuite in a browser tab

What Grid does

From the app’s own documentation, version 0.14.2.

Tools

  • 500+ worksheet functions, plus LET, LAMBDA, MAP, REDUCE and BYROW
  • Dynamic arrays that spill
  • Pivot tables saved to and read from XLSX
  • Seventeen chart types with a Format pane
  • Sort, AutoFilter, Flash Fill and data validation
  • Conditional formatting, colour scales and sparklines
  • Structured table references
  • Page Break Preview and PDF export

Files it opens

XLSXCSVTSVXLS (values and formulas)XLSB and ODS (data)

Files it saves

XLSXCSVTSVPDF

Not there yet

  • Formatting and objects from old .xls files
  • Formulas from XLSB and ODS (their saved values come in)
  • Very large workbooks and multi-threaded recalculation

What Grid replaces

The paid apps people use for the same job. Prices from the vendors’ US pages on 14 November 2026.

Grid instead of Excel

Excel costs US$99.99 a year (or US$9.99 a month) for Microsoft 365 Personal.

Read the comparisonGrid instead of Microsoft 365

Microsoft 365 costs US$99.99 a year (or US$9.99 a month) for Microsoft 365 Personal.

Read the comparison

Open a file with Grid

Open .xlsx files

The spreadsheet format of Microsoft Excel since 2007: sheets, formulas, charts and pivot tables.

Open .xlsb files

Excel’s binary workbook format, used for large spreadsheets.

Grid questions

Is Grid free?

Yes. Grid is part of Madosuite, which is free. It runs in your browser on your own device.

Which files does Grid open?

XLSX, CSV, TSV, XLS (values and formulas), XLSB and ODS (data). It saves XLSX, CSV, TSV, PDF.

Is Grid ready for real work?

Alpha: its makers rate it the core workflow works end to end; depth and file compatibility are still rough. Not there yet: formatting and objects from old .xls files; formulas from xlsb and ods (their saved values come in); very large workbooks and multi-threaded recalculation.

Can Grid replace Excel?

For budgets, data, formulas, pivot tables and charts, often yes, and free. Grid is alpha: formatting from old .xls files does not come in, and very large workbooks are next on its list.

Where are my files kept?

In the browser on your device, inside Madosuite’s own Linux machine, in its home folder. Your files are not uploaded to us. Clearing the site’s data in your browser deletes them, so download what you want to keep.

Who makes the apps?

The suite apps are the ArtCraft team’s open-source Crafting Apps, under the MIT or Apache-2.0 licence. Madosuite puts them on one desktop in your browser, with Files, a Terminal and Edix, the code editor. See credits.

More apps in Madosuite

Word

Write and lay out documents with the ribbon, styles, tables, track changes and references you already know, and save real .docx files.

Deck

Build slide decks with themes, charts, transitions and animations, open and save .pptx, and present full screen.

Photo

Edit images with layers, masks, adjustment layers, layer styles and type, and open and save real .psd files.

Vector

Draw with the Pen, Pathfinder and Shape Builder across many artboards, and open .ai, .svg and .pdf files.

Grid is GridCraft 0.14.2 by the ArtCraft team, open source under MIT or Apache-2.0. Credits.