How to use Excel to JSON
- 1
Open the Excel to JSON converter
Go to tools.slaytic.com and open the Excel to JSON tool. No sign-up or account required.
- 2
Drop your Excel file
Drop your .xlsx or .xls file onto the tool, or click to browse and select it. If it has more than one sheet, a picker appears so you can choose which one to convert.
- 3
Copy or download your JSON
The selected sheet converts to a JSON array instantly. Copy it to your clipboard or download it as a .json file - no waiting, no email, no cloud storage.
How this works in your browser
This tool uses SheetJS, the same open-source spreadsheet library that powers Excel to CSV and CSV to Excel on this site, loaded on demand only when you actually use a spreadsheet tool. It parses your workbook’s binary format directly in your browser tab and reads each sheet’s cell grid into memory. Converting to JSON is then a matter of treating your first row as field names and mapping every row beneath it into one object per row, all without a server ever seeing the file.
Excel to JSON vs. traditional online converters
| Feature | Excel to JSON (in-browser) | Traditional online converters |
|---|---|---|
| File upload required | No - never leaves your device | Yes - file is sent to a server |
| Processing queue | None - starts instantly | Often, especially at peak times |
| Watermark on output | Never | Common on free plans |
| Usage limits | None - free, unlimited use | Often capped per day or file size |
| Works offline once loaded | Yes, for most tools | No - requires a live connection |
| Account required | No | Often, for anything beyond a trial |
Who uses Excel to JSON
Frontend and mobile developers
Turn a spreadsheet of product, content, or config data into JSON that drops straight into an app or a mock API, without hand-typing it.
Data analysts
Export a specific sheet from a larger workbook as JSON for a script or notebook that expects structured data instead of a binary Excel file.
QA and test engineers
Convert a spreadsheet of test cases or fixtures into JSON test data in seconds.
Frequently asked questions
Is this Excel to JSON converter free?
Yes, completely free with no limit on file size or how many workbooks you convert.
Does it support multiple sheets?
Yes. If your workbook has more than one sheet, a picker appears after it loads so you can choose which sheet to convert, without needing to split the file first.
What happens to empty cells?
Empty cells are output as null in the JSON, so every row object has the same set of keys, rather than some rows silently missing a field.
Are formulas converted to their calculated values?
Yes. JSON has no concept of formulas, so cells are exported as the value Excel last calculated for them.
Is my spreadsheet uploaded anywhere?
No. The file is read and converted entirely inside your browser tab using SheetJS; it never leaves your device.