🔀 JSON ↔ CSV Converter

About

This tool converts between JSON (an array of objects) and CSV entirely on your device — your data never leaves the browser. A quote-aware CSV parser correctly handles fields that contain commas, newlines, or escaped double-quotes, so complex exports from spreadsheets or databases round-trip without corruption. You can paste data directly into the editor, or load a .json or .csv file from disk. Results can be copied to the clipboard or downloaded as a file. Because everything runs offline, the tool works without an internet connection after the page loads.

How to use

1. Choose a direction: JSON → CSV or CSV → JSON using the toggle at the top of the tool.
2. Paste your data into the input box, or click the load button to open a .json or .csv file from your device.
3. Click Convert. The result appears instantly in the output box below.
4. Click Copy to copy the output to your clipboard, or Download to save it as a file.

FAQ

What JSON structure does the converter expect?

The input must be a JSON array of objects where every item shares the same keys. Each object becomes one CSV row; the keys of the first object become the header row.

Does the CSV parser handle quoted fields with commas or newlines inside them?

Yes. The parser follows RFC 4180: fields enclosed in double-quotes may contain commas, newlines, and escaped quotes. A doubled quote inside a quoted field represents a literal quote character.

Is my data sent to a server?

No. All parsing and conversion runs in your browser with JavaScript. Your data never leaves your device.

What happens if objects in the JSON array have different keys?

The header is built from the union of all keys found across every object. Missing values for a given row are output as empty cells in the CSV.

Does CSV to JSON coerce types automatically?

Yes. Plain numeric strings become numbers, and the literal strings true and false become boolean values. All other values remain strings.