CSV ↔ JSON Converter
Convert between CSV and JSON
Converting between CSV and JSON
CSV is what spreadsheets and database exports produce; JSON is what web APIs and configuration files expect. The mismatch shows up constantly — the file came from Excel as CSV, but the script needs JSON. This tool converts in either direction, one at a time, entirely in the browser.
For CSV → JSON you choose the delimiter (comma, tab or semicolon) and whether the first row is a header. With a header, you get an array of objects keyed by column name; without one, you get an array of arrays. For JSON → CSV, pass an array of objects and the keys become the header row. The copy button puts the result straight on your clipboard.
Because everything runs locally, you can paste the contents of files you would not want to upload — customer lists, revenue exports, internal reports. If the input is malformed the tool reports an error rather than producing garbage, which makes truncated CSV or JSON with a trailing comma easy to spot.
Frequently asked questions
- Does it support tab-separated files (TSV)?
- Yes. Select tab as the delimiter to read TSV. Semicolon-delimited CSV, common in some locales, is supported too.
- What happens if the first row is not a header?
- Turn the header option off and each row becomes an array of values, so the output is an array of arrays.
- Can JSON → CSV handle nested objects?
- It expects a flat array of objects. Flatten nested values first, since a single CSV cell cannot represent a nested structure.
- Is my data uploaded?
- No. Conversion happens entirely in your browser and nothing you paste is sent to a server.
