Excel to JSON Converter
Data ConversionRead an .xlsx workbook straight into JSON, one sheet at a time.
Runs entirely in your browser — nothing is uploaded
Features
- Opens .xlsx workbooks with no upload and no server.
- Picks up every sheet, so you can choose which one to convert.
- Types numbers and booleans back from the cell values.
- Reads cached formula results, so calculated columns come through.
- Array of objects or newline-delimited JSON output.
- Duplicate headers are suffixed instead of overwriting each other.
How to use the Excel to JSON Converter
- 1Drop an .xlsx workbook onto the box.
- 2Pick the sheet and confirm whether the first row is a header.
- 3Copy the JSON or download it.
Frequently asked questions
How can it read a spreadsheet without uploading it?
An .xlsx file is a ZIP archive full of XML. The browser unzips it and reads the cell values directly in the tab, so the workbook never leaves your device.
Do formula cells work?
Yes — you get the last value Excel calculated, which it stores in the file alongside the formula. The formula itself is not re-evaluated, so if the workbook was saved without recalculating, the value will be the stale one Excel had.
Why is my .xls file rejected?
The legacy binary .xls format is a completely different file format from .xlsx and would need a separate parser. Rather than half-read it into nonsense, it is rejected with instructions: open it in Excel, Google Sheets or LibreOffice and save as .xlsx.
What happens to merged cells and formatting?
Only the values are read. Colours, borders, merged ranges and charts have no JSON equivalent, so they are ignored — a merged cell contributes its value once, in its top-left position.
Can I convert a CSV here?
Use the CSV to JSON tool instead — it reads a .csv directly, so there is no need to open it in Excel and re-save it first.