Convert an Excel XLSX spreadsheet to CSV - perfect for scripts, data tools, or systems that won't open .xlsx.
XLSX is great for humans but awkward for scripts: it's a ZIP archive of XML files, formulas need evaluation, and dates have a weird epoch. CSV is the universal data exchange format - every scripting language and data tool reads it natively. Converting XLSX to CSV lets you feed Excel-authored data into pipelines and APIs that expect simple tabular text.
We use SheetJS to parse the .xlsx, evaluate formulas, and emit the first sheet as CSV with proper RFC 4180 quoting. Dates render in ISO 8601 format. For multi-sheet workbooks, only the first sheet is converted - this matches what 90% of users actually want. Everything runs in your browser; the workbook never leaves your device.
XLSX is Microsoft Excel's default spreadsheet format - a ZIP archive of XML files. Supports formulas, multiple sheets, charts, and styling. The de-facto business data exchange format.
CSV (Comma-Separated Values) is the simplest tabular format - plain text rows of comma-delimited values. Read by every spreadsheet program, scripting language, and data tool ever made.
Drag a XLSX onto the converter above, or click the box to pick one from your device.
We've preselected CSV as the output format. Change it from the dropdown if you want a different target.
Click Convert and wait for the progress bar to finish. Download the CSV when it's ready.
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