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.xlsx

XLSX test files

Real Excel workbooks with several sheets, typed cells and formulas stored as formulas, for testing imports, converters and spreadsheet code.

Open the .xlsx generator

Or start from a preset

What is a XLSX file?

Short answer

An XLSX file is an Excel workbook in the Office Open XML format: a ZIP package with one XML part per sheet, a shared string table, styles and a workbook part that lists the sheets.

Readers trip on the details: dates are numbers with a date style, formulas carry a cached value, text lives in a shared string table, and errors like #DIV/0! have their own cell type. The generator writes each the way Excel does.

Anatomy of a XLSX file

  • xl/workbook.xmlThe sheet list and calculation settings
  • xl/worksheets/sheet1.xmlRows and cells of one sheet
  • xl/sharedStrings.xmlEvery text value, stored once
  • xl/styles.xmlNumber formats: dates, money, wrapped text
  • <f>D2*E2</f>A formula, with its cached value in <v>

What you can generate

  • 1 to 10 sheets, up to 100,000 rows each
  • Formulas (D*E per row, SUM at the bottom) with cached values
  • Dates as serial numbers with a yyyy-mm-dd format
  • Merged title row and frozen header
  • Booleans and #DIV/0! errors
  • Long wrapped text and Unicode, including the sheet name

How to make one

  1. Open the XLSX generator, or start from a preset above.
  2. Set the size and switch on the edge cases you need; the preview and size estimate follow every change.
  3. Generate, then download. The file is made in your browser, and the same preset and seed always give you the same file.

Questions

Yes. Total cells hold =D2*E2 and the last row =SUM(...), with cached values, and the workbook asks Excel to recalculate on open.

The package follows the ECMA-376 part and element order, and the tests check every part, relationship and shared-string index. Charts are not written yet.

That is how XLSX stores them: days since 30 December 1899, shown as dates through the cell's number format.

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