Private browser data tool
Convert CSV and JSON without sending data anywhere.
Move structured data between formats in one tab. Paste text or choose a local file, then convert and download the result without an account or server upload.
CSV ↔ JSON Converter
Use a sample first, or bring your own local text.
Choose a sample or add your own input.
Your text and selected file are read by this tab only. The converter does not upload or store them. Shared page assets and advertising are described in the privacy policy.
CSV and JSON conversion questions
Does this CSV converter upload my data?
No. CSV and JSON conversion runs in this browser tab. The page does not upload, store, or share your input.
Which delimiters are supported?
CSV to JSON mode detects comma, tab, and semicolon delimiters. Quoted fields can contain commas, quotes, and line breaks.
What JSON can I convert to CSV?
JSON to CSV mode accepts a non-empty array of objects. Keys become the header row and later objects can add columns.
How do I convert CSV to JSON or JSON to CSV?
Choose a direction, paste text or select a local file, and choose Convert. CSV mode detects comma, tab, and semicolon delimiters; JSON mode accepts an array of objects and turns its keys into the CSV header.
Worked example
Use the sample to see the expected shape, then replace it with your own rows. Quoted CSV fields can contain commas, quotes, and line breaks. Copy the result or download `converted.json` or `converted.csv`.
Limits to know
The input is limited to 1 MiB and is processed in this browser tab. JSON to CSV accepts a non-empty array of objects; nested values are written as JSON text inside an escaped CSV cell. Nothing is uploaded or stored.