CSV to JSON
Turn a spreadsheet or CSV export into clean JSON for your code, API or database.
- Your data never leaves your device
- 100% free
- No sign-up
- Works offline after first load
How to convert CSV to JSON
- Paste CSV or open a CSV, TSV or Excel file.
- Check the detected delimiter and header, choose types and output shape.
- Copy or download the JSON.
About CSV to JSON
Convert CSV, TSV or Excel sheets to JSON.
Everything works in your browser, so it is instant and private, and your settings are remembered on this device.
Good for
- Loading spreadsheet data into apps and APIs
- Creating test fixtures and seed data
- Converting exports for JavaScript and NoSQL databases
Tip: If your values contain commas, make sure they are quoted — the parser follows RFC 4180, so "Pune, India" stays one value.
Frequently asked questions
Which files can I convert?
CSV and TSV with any delimiter (comma, semicolon, tab or pipe), and Excel / LibreOffice files (.xlsx, .xls, .ods) — the first sheet is converted.
Are numbers and true/false converted?
Yes, with “Detect numbers, true / false and null” on. Values with leading zeros (like 007) and very long numbers stay text so nothing is lost.
Can it create nested JSON?
Yes — turn on “Nest dotted headers” and a column named address.city becomes {"address": {"city": …}}.
What output shapes are there?
An array of objects (most common), an array of arrays, an object keyed by the first column, an object of columns, or JSON Lines for streaming and big data tools.
Is my data uploaded?
No. Everything is processed by JavaScript in your browser — nothing you paste or open is sent to a server, so it is safe for API responses, tokens, configs and customer data. It also works offline once the page has loaded.