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XLSX to JSON

Sheets, cells, values, types, formulas and merged ranges — as a developer wants them.

More free conversions, where you upload. The Fylane extension does the same work inside any upload form, on its own free share every day.About the extension

How to convert XLSX to JSON

  1. Drop the file.
  2. Nothing to choose.
  3. Press Convert and download.

What happens to your file

The workbook is read directly — it is XML in a zip — on Fylane’s servers: sheet names, each cell’s reference, value and type (number, string, boolean, error, empty), its formula where it has one, and the merged ranges. Dates come out as the serial numbers Excel stores, labelled as numbers: converting them needs the cell’s format, and a guessed date is worse than an honest serial.

Twenty sheets and five thousand rows a sheet at most; the report says when a sheet was cut.

Questions

Why are my dates numbers?

Excel stores a date as days since 1900. The number is exact; the format that shows it as a date is a display choice, so it is handed back as stored.

CSV in?

Not here — this reads XLSX. CSV to Excel first, or use Excel to CSV the other way.

Do this in code

curl -X POST https://api.fylane.dev/v1/jobs \
  -H "Authorization: Bearer $FYLANE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "file_id": "<file id>",
    "operation": "sheet.parse",
    "options": {}
  }'

The same operation, sheet.parse — The workbook itself: sheets, values, types, formulas, merged ranges — dates as the serials Excel stores. Upload first with the quickstart; every option is on the operations page. 500 free credits a month, then $5 per thousand.