How to use the Excel to JSON Converter
- 1. Choose a workbookPick an .xlsx, .xls, .ods or .csv file.
- 2. Pick the shapeObjects keyed by the header row, or plain arrays; decide how to treat empty cells.
- 3. ConvertCopy the JSON or download a .json file.
How cells become JSON
With array of objects, the first row becomes the keys and every later row becomes one object. Numbers stay numbers, TRUE/FALSE become true/false, and dates become "YYYY-MM-DD" strings, so the output works straight away in JavaScript, Python or a database import. Empty cells can become null, be left out, or become empty strings. Empty headers get keys like column_3, and repeated headers get Name_2, so no data is overwritten. Choosing All sheets gives one object keyed by sheet name. Files are read by your browser and never uploaded.
Worked example
A sheet with headers Name, Course, Fee and Joined, and a row Asha · Python · 25000 · 3 April 2026, becomes {"Name": "Asha", "Course": "Python", "Fee": 25000, "Joined": "2026-04-03"}. The fee is a number, not the text "25000", and the date is in a format every language can parse.
Limits
- Nested JSON isn't built from dotted headers; every key stays flat.
- Very large sheets produce large JSON. The page previews the first 2,00,000 characters, but the download has everything.
- Formulas are exported as their last calculated values.
- Times and date-times are exported as text in ISO format; check time zones if you load them into an app.
Typical uses
Developers use this to turn a product, price or city list kept in Excel into a JSON seed file for an app or API. Students use it to turn a marks sheet into data for a JavaScript project. Testers use it to make test-data files from a spreadsheet the business team maintains.
Frequently asked questions
Can I go the other way, JSON to Excel?
Convert JSON to CSV with our JSON to CSV tool, then use the CSV to Excel converter.
Is the JSON valid?
Yes. It's produced with the browser's own JSON.stringify, so it's always valid JSON.
Is the Excel to JSON converter free?
Yes. You can open the Excel to JSON converter, load files and set every option without signing up. When you convert a file for the first time, we ask once for your name and WhatsApp number; after that it, and every other Uncodemy tool, opens straight away.