JSON ↔ CSV Converter
Convert between JSON arrays and CSV format instantly.
About JSON ↔ CSV Converter
APIs speak JSON, spreadsheets speak CSV, and moving data between the two by hand is tedious and error-prone. This free JSON to CSV converter online works in both directions: paste a JSON array of objects to get clean, spreadsheet-ready CSV, or paste comma-separated data with a header row to get neatly formatted JSON. There is no sign-up and no file upload to a server — the entire conversion runs locally in your browser, so your data never leaves your device.
The converter handles the messy details for you. Nested JSON objects are automatically flattened into dot-notation columns (an address object becomes address.city and address.zip), fields containing commas, quotes, or line breaks are properly escaped, and columns are unified even when objects have different keys. A live preview table shows the first rows of your result so you can sanity-check the structure before you export, then copy the output to your clipboard or download it as a .csv or .json file in one click.
How to convert JSON to CSV (and back)
- 1Choose your direction with the JSON → CSV or CSV → JSON tab at the top.
- 2Paste your data into the input box — a JSON array of objects for JSON to CSV, or comma-separated rows with a header line for CSV to JSON.
- 3Click Convert. If the input is malformed, a clear error message explains what to fix.
- 4Review the output box and the preview table, which shows the first 10 rows of the converted data.
- 5Click Copy to put the result on your clipboard, or Download to save it as a .csv or .json file.
Frequently asked questions
What JSON structure does the converter expect?
A JSON array of objects, such as a typical API response list. Each object becomes one CSV row, and the union of all keys becomes the header row. Nested objects are flattened into dot-notation columns — for example user.address.city — while missing keys simply produce empty cells.
What CSV format does CSV to JSON expect?
Standard comma-delimited CSV with a header row followed by at least one data row. The header names become the JSON keys. Quoted fields are fully supported, including commas inside quotes and escaped double quotes, and the output is pretty-printed JSON with two-space indentation.
Can I use semicolons or tabs as the delimiter?
Not currently — the converter reads and writes comma-delimited CSV, which is what Excel, Google Sheets, and most data tools expect by default. If your file uses semicolons, replace them with commas (taking care with quoted fields) before pasting.
Is my data uploaded to your servers?
No. The conversion runs entirely in your browser with JavaScript — nothing you paste is transmitted, logged, or stored anywhere. That makes it safe to convert customer exports and other sensitive tabular data.
Is there a limit on how much data I can convert?
There is no fixed row or size limit. Because everything runs in your browser, very large datasets are bounded only by your device’s memory — typical exports of thousands of rows convert instantly.
Is this JSON CSV converter free?
Yes — completely free, with no sign-up, no watermarks, and no usage limits.
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