Excel to JSON Converter – Convert Excel Online (Free Tool)
Convert Excel files to JSON format. Transform spreadsheet data into structured JSON objects.
Example Output
Pretty-printed JSON array. Each cell becomes a property typed as string/number/boolean/null based on the underlying Excel cell type.
employees.json — array of 1,800 objects keyed by the first-row headers
What is Excel to JSON Converter?
Convert Excel spreadsheets (.xlsx, .xls) into clean JSON arrays without uploading the file anywhere. The converter reads the chosen sheet, treats row 1 as the keys, and preserves Excel cell types (numbers stay numbers, dates become ISO strings, blanks become null) so the output drops straight into APIs, databases, or front-end apps.
Why use this tool?
- Lightweight page weight that loads quickly even on slow connections
- Works on desktop, tablet, and mobile in any modern browser
- Stable behavior across visits — no surprise version drift
- Auto-detects encoding (UTF-8, Shift_JIS, GBK, Vietnamese) for CSV imports
- No file upload — confidential reports never leave your computer
How to use
- Upload your Excel file
- Select the sheet to convert
- Choose JSON format (array of objects)
- Download or copy the JSON output
Examples
API seed data
A product catalogue maintained in Excel becomes a JSON array your seed script can post to /products in one curl loop.
Multi-sheet workbook
Pick which sheet to convert; the others are ignored. Useful when finance keeps `Inputs` and `Outputs` in the same file.
Nested keys via dot notation
Headers like `address.city` and `address.zip` are turned into nested objects automatically — no manual restructuring needed.
Common use cases
- Loading Excel-maintained data into a JavaScript or Python app
- Feeding spreadsheet content to a REST/GraphQL API
- Seeding a database from a non-technical owner's workbook
- Generating fixtures for unit and integration tests
- Powering charts and dashboards in front-end apps
Troubleshooting
- Dates appear as numbers like 45200
- Excel stores dates as serial numbers. Toggle the "convert dates to ISO 8601" option so 45200 becomes "2023-09-26".
- Some rows are missing from the JSON
- Hidden rows or filtered rows are skipped if "include hidden rows" is off. Re-run with that option enabled.
- Duplicate keys in the output
- Your header row has duplicate column names. Rename them in Excel — JSON object keys must be unique.
Frequently Asked Questions
The first row becomes the JSON keys; each subsequent row becomes one object. So a sheet with columns Name/Age/Email gives `[{"Name": "...", "Age": 30, "Email": "..."}, ...]`.
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