Your files stay on your device
XLSX Reader and Writer: Inspect, Convert, Build Workbooks
Inspect a workbook (sheets, used ranges, formulas, merges), convert any sheet or range to CSV, TSV, JSON, HTML, or Markdown with dates and numbers formatted, and build an XLSX from CSV or JSON.
Input kind
- No recalculation. Formula cells ship their cached results, as stored by the app that saved the file.
- The writer is minimal on purpose: values, types, date serials, and sheet names; no styling, formulas, charts, or macros, ever.
- Reader: styling, charts, and macros do not survive conversion; number formats apply to table output through a bounded code subset.
- .xls (pre-2007 binary) is not a ZIP container and is refused by the signature check.
Nothing in yet
Paste, drop, or type to begin. Everything stays on this device.
load an .xlsx, pick a sheet, convert