Free & private — nested JSON flattened automatically. Nothing is uploaded; conversion runs entirely in your browser.
How to convert JSON to CSV
1) Paste your JSON (or drop a file) in the input box. 2) Pick a delimiter — comma for Excel, semicolon for many European locales, tab for spreadsheets. 3) Click Convert, then copy or download the CSV. There is no file-size cap, no sign-up, and no daily limit because everything runs locally on your device.
How nested JSON is handled
Nested objects are flattened into dot-notation columns, so this…
{"user":{"name":"Ann","address":{"city":"Lisbon"}}} …becomes columns user.name and user.address.city. Arrays and values that cannot be flattened are kept as JSON strings so no data is ever lost. Turn off "Flatten nested objects" to keep nested values in a single cell.
Converting CSV back to JSON
Switch to the CSV → JSON tab, paste your CSV (the delimiter is auto-detected), and you get a typed JSON array — numbers, booleans and nulls are inferred automatically.
Frequently asked questions
Is this JSON to CSV converter really free?
Yes — free with no sign-up, no row limits and no watermarks. The tool is static and hosted on a CDN, which keeps our costs near zero.
Is my data private?
Completely. All conversion happens in your browser with JavaScript. Your JSON/CSV is never uploaded, stored or logged. See our privacy policy.
What file sizes can I convert?
There is no artificial limit. Very large files (tens of MB) depend on your device memory, but because processing is local there is no server queue or upload wait.
Can it handle arrays of objects?
Yes — an array of objects becomes one CSV row per object, with the header built from the union of all keys in order of first appearance.
Which delimiter should I use?
Comma is the default and works with most tools. Choose semicolon if your Excel locale uses it, or tab for TSV-style output.