Excel to JSON
Convert Excel or CSV to JSON — objects from the header row, nested keys, real numbers and ISO dates, every sheet, with a live preview.
- Files never leave your device
- 100% free
- No sign-up
- No watermark
- Works offline after first load
or drag & drop Excel, ODS or CSV files here
How to convert Excel to JSON
- Select or drop an Excel, ODS or CSV file. The first row should hold the names you want as JSON keys.
- Choose the shape (array of objects, array of arrays, keyed object, columns or JSON Lines), which sheets to include and how empty cells and dates are written. The preview updates as you go.
- Click Convert to JSON to download the .json file, or copy it from the preview.
About Excel to JSON
Turn a spreadsheet into JSON for an API, a web app or a database. Each row becomes an object with keys from the header row, numbers and TRUE/FALSE stay real values, and dates become ISO dates — or choose an array of arrays, an object keyed by an ID column, columns, or JSON Lines.
Dotted headers like address.city build nested objects, keys can be turned into camelCase, empty cells can be left out or written as null, and every sheet can be converted at once. A live preview shows the result as you change the options, and nothing is uploaded.
Good for
- Seeding a database or mock API from a spreadsheet
- Turning product or translation sheets into app data
- Preparing data for JavaScript, Python or no-code tools
Tip: Name columns like customer.name and customer.email to get nested objects.
Frequently asked questions
What JSON does it make?
By default an array of objects: each row becomes an object whose keys are the header row, like [{"name": "Asha", "amount": 1250.5}]. You can also get an array of arrays, an object keyed by the first column, an object of columns, or JSON Lines.
Can I create nested JSON?
Yes. Name columns with dots — address.city and address.zip — and they become nested objects: "address": {"city": …, "zip": …}.
Are numbers and dates kept as the right types?
Numbers and TRUE/FALSE become real JSON numbers and booleans; dates become ISO dates like 2024-03-31 (or as shown in Excel). Untick the option to get all values as text.
What happens to empty cells?
You choose: leave the key out, write null, or write an empty string.
Can I convert every sheet?
Yes — as one JSON object with a key per sheet name, or as a separate JSON file per sheet.
Can I make keys camelCase?
Yes. Tick “Make keys camelCase” and headers like First Name become firstName.
Are my files uploaded?
No. The conversion happens entirely in your browser — your data never leaves your device.