Developer tools
CSV to JSON converter
Paste CSV to convert it to JSON, or switch direction to turn JSON back into CSV. Pick a delimiter, choose whether the first row is a header, and check the live preview. Everything runs in your browser - nothing is uploaded.
How it works
Paste CSV and get a JSON array, or paste JSON and get CSV back. By default the first CSV row is treated as the header, so each following row becomes a JSON object keyed by those column names; turn the header option off and rows become simple arrays instead. The delimiter is configurable - comma, semicolon, or tab - for data exported from different tools and locales, and quoted fields containing the delimiter or line breaks are handled correctly.
Going the other way, a JSON array of objects is flattened back into CSV, with a header row built from the keys. A live preview table shows the parsed data so you can confirm the columns line up before copying. Everything runs in your browser, so your data is never uploaded.
Example. Paste name,age then Ada,36 and Linus,54 on the next lines, keep the header option on, and you get [{"name":"Ada","age":"36"},{"name":"Linus","age":"54"}]. Switch the delimiter to semicolon for data exported by a spreadsheet that uses it, and the columns split correctly.
FAQ
Does it handle quoted fields and commas inside values?
Yes. The parser follows the usual CSV quoting rules: a field wrapped in double quotes can contain the delimiter, line breaks, and escaped double quotes (written as two double quotes). So a value like "Smith, John" stays a single field rather than splitting into two columns.
What does the header row option do?
With it on, the first CSV row is read as column names and each data row becomes a JSON object using those names as keys. With it off, every row including the first is treated as data and becomes a JSON array of values. Turn it off when your CSV has no header line, or when you want positional arrays rather than named fields.
Can I convert JSON back to CSV?
Yes. Paste a JSON array of objects and the tool builds a CSV with a header row from the object keys and one row per object, quoting any value that needs it. It works best when the objects share the same keys; missing keys become empty cells so the columns stay aligned.
Is my data uploaded?
No. Parsing and converting happen entirely in your browser. Nothing you paste is sent to a server, logged, or stored, so it is safe to convert private spreadsheets or exports.