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JSON ↔ CSV Converter

Convert between JSON and CSV — round-trip safe, runs locally.

Runs in your browserNo account requiredNo uploadFree
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About JSON ↔ CSV Converter

JSON ↔ CSV Converter turns an array of JSON objects into a comma-separated table, and turns a CSV table back into a JSON array. It exists for the everyday job of moving data between something that speaks JSON — an API response, a code file, a database export — and something that speaks CSV, like a spreadsheet or a bulk-import form.

Pick the direction (JSON → CSV or CSV → JSON) and paste your data. Given the array [{"name":"Ada","role":"Engineer"},{"name":"Bo","role":"Designer"}], you get a CSV with a name,role header row and two data rows beneath it. Paste that CSV back and you get the original array of objects again. Column headers are taken from the object keys; if some objects are missing a key, that cell is simply left blank.

Because CSV is a flat format, it cannot represent nesting the way JSON can. Rather than dropping a nested object or array, the tool serializes it into its cell as a JSON string. Values that contain the delimiter, double quotes, or line breaks are quoted and escaped following the RFC 4180 convention, so the output opens cleanly in Excel, Google Sheets, and Numbers. You can switch the delimiter between comma, semicolon, and tab.

The conversion runs entirely in your browser — no upload, no account, nothing logged. Customer lists, order exports, and other potentially sensitive tabular data stay on your own machine.

Frequently asked questions

CSV is a flat format and cannot nest. A nested object or array is written into its cell as a JSON string rather than being lost, so no data is dropped.

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