Question 1

How do I convert Excel to JSON?

Accepted Answer

Upload your .xlsx or .xls file, choose a sheet if there are multiple, select the output format (array of rows or array of objects with header keys), and the JSON appears instantly. Copy or download it from the toolbar.

Question 2

What is the difference between row array and header-key format?

Accepted Answer

Row array format outputs each row as a simple array of values: [["Name","Age"],["Alice",30]]. Header-key format uses the first row as keys: [{"Name":"Alice","Age":30}]. Header-key is usually better for APIs and apps.

Question 3

Does it support multiple sheets?

Accepted Answer

Yes. If your workbook has multiple sheets, a dropdown appears letting you choose which sheet to convert. Each sheet can be converted independently.

Question 4

Is my spreadsheet data uploaded to a server?

Accepted Answer

No. The spreadsheet is parsed entirely in your browser using the SheetJS (xlsx) library. Your data never leaves your computer.