Why convert Excel to JSON in the browser?
Spreadsheets are where business data lives; JSON is what modern software speaks. Analysts, developers, and operations teams constantly need to move data from one to the other — and the typical route, uploading your workbook to a conversion website, quietly hands a copy of that workbook to a third party.
That matters more with Excel files than almost any other format, because spreadsheets so often contain the sensitive stuff: salary tables, customer exports, sales pipelines, project budgets. This converter removes the risk entirely by doing the work on your device. The file is opened with the SheetJS parsing library inside your browser tab, converted to JSON in memory, and never transmitted anywhere.
- No uploads — the workbook never leaves your computer
- Supports .xlsx and .xls — modern and legacy Excel formats
- Header-aware — your first row becomes the JSON keys
- Free and unlimited — no account, no row caps
How to convert an Excel file to JSON
- Drag your .xlsx or .xls file onto the drop area above (or click it to browse).
- The first worksheet is read instantly; the first row is treated as column headers.
- Review the JSON output on the right.
- Click Copy or Download .json.
What the output looks like
Each spreadsheet row becomes a JSON object keyed by your header row — the structure expected by APIs, JavaScript applications, and document databases:
[
{ "Product": "Widget A", "Q1 Sales": "1200", "Region": "EMEA" },
{ "Product": "Widget B", "Q1 Sales": "950", "Region": "APAC" }
]
Formulas are exported as their calculated values, and empty cells become empty strings, so the output is predictable and safe to feed into scripts.
Common use cases
- Feeding web apps — turn business-owned spreadsheets into data a frontend can consume
- API payloads — convert an Excel export into the JSON body an endpoint expects
- NoSQL imports — prepare spreadsheet data for MongoDB, Firestore, or other document stores
- Automation — one-off conversions during scripting or ETL prototyping, without writing parser code
Frequently asked questions
Is it safe to convert confidential Excel files here?
Yes. Your spreadsheet is read and converted entirely inside your browser. The file is never uploaded to a server, so confidential data such as payroll, client lists, or financials stays on your device.
Which Excel formats are supported?
Both modern .xlsx workbooks and legacy .xls files. The converter reads the first worksheet in the workbook.
What happens to formulas and formatting?
The converter exports the calculated values of cells, not the formulas. Visual formatting (colors, fonts, column widths) is not part of JSON and is not included.
Does it convert multiple sheets?
Currently the first worksheet is converted. If you need a different sheet, move it to the first position in Excel, or copy it into a new workbook before converting.
Is this Excel to JSON converter free?
Yes, completely free — no account, no row limits, and no watermarks.
Related tools
Working with CSVs instead? Use the CSV to JSON converter. Turning notes or prompts into structured documents? Try text to Markdown. For deduplication, cleaning, and exporting to CSV/Excel/JSON in one place, open the full Data Transformer toolkit.