XLSX → JSON Converter
Load an .xlsx and convert it to JSON in the browser — clean data rows for apps & AI, or the lossless ReoGrid JSON workbook. Toggle, copy, download.
How it works
A developer-focused converter: load any .xlsx in the browser and turn it into JSON two ways. Toggle between app-friendly data rows and the lossless ReoGrid JSON workbook, then copy or download the result. Everything runs client-side — the file never leaves the browser.
- grid.loadFromFile(file) parses the .xlsx into the grid entirely in the browser, one worksheet per sheet
- Data rows mode walks getExportSnapshot() for the used range and reads worksheet.getDisplayText(r, c) — the rendered value with formulas evaluated and number formats applied
- ReoGrid JSON mode calls grid.toJson() for the full lossless document (styles, formulas, merges, cell types)
- Copy / Download act on the full JSON string; the on-screen preview is capped for large files
- No upload, no backend — paste the data rows straight into an API request, a database import, or an LLM prompt
Key APIs used
grid.toJson() Serialize the whole workbook to a lossless ReoGrid JSON document
worksheet.getDisplayText(r, c) Read the rendered cell value (formulas evaluated, number formats applied) for building data rows
worksheet.getExportSnapshot() Sparse list of populated cells — used to find the data extent
grid.loadFromFile(file) Parse an .xlsx File object in the browser and load every sheet in it
Source Code
Related Documentation
Related Articles
Convert XLSX to JSON in the browser — no server
Lossless ReoGrid JSON vs plain data rows, entirely client-side.
From Excel to your app: extract structured data as JSON
Header detection, type coercion, multi-sheet, and a POST to your API.
Batch-process spreadsheet data with AI: xlsx → JSON → LLM
Send the JSON rows to Claude and write the results back into the grid.