Excel to JSON

Spreadsheets are where business data lives, but applications, APIs and databases want JSON. This converter reads an Excel workbook or CSV file in your browser and turns the first sheet into a JSON array, using the header row as object keys. No upload is involved, so it is safe for customer lists, price sheets and internal reports.

How to use it

1. Select an .xlsx, .xls or .csv file.
2. Make sure the first row contains column headers.
3. Copy or download the generated JSON.

Example

A sheet with headers sku, name, price and rows A-100, Desk lamp, 24.5 and A-101, Monitor arm, 59 becomes an array of two objects, each with sku, name and price fields. Numeric cells are output as numbers, text cells as strings.

Preparing your sheet

• One header row with unique, simple names. Merged header cells and multi-row headers produce awkward keys.
• No blank rows in the middle of the data.
• Consistent types per column: a column mixing numbers and text arrives mixed in JSON.
• Dates: Excel stores dates as serial numbers (days since 1900). Format date columns as text in ISO format, such as 2026-10-27, if you need predictable output.
• Leading zeros: postal codes and phone numbers lose leading zeros if stored as numbers; format those columns as text.

Limitations

Only the first worksheet is converted. Formulas are exported as their calculated values, and formatting, comments and charts are ignored.