CSV ⇄ JSON Converter
Convert CSV to JSON or JSON to CSV instantly in your browser · free, no signup
Free CSV to JSON and JSON to CSV Converter
Spreadsheets export as CSV, but APIs and scripts usually need JSON — and going the other way is just as common when you need to open API data in Excel or Google Sheets. This tool detects which direction you need automatically: paste CSV and it produces an array of JSON objects using your header row as keys, or paste a JSON array of flat objects and it produces a CSV with those keys as columns.
It auto-detects common delimiters (comma, semicolon, tab) in CSV input, handles quoted fields containing commas or line breaks correctly, and shows a live table preview of the result so you can catch column mismatches before downloading. Nested JSON objects are flattened with dot notation so they still fit into CSV columns.
Key features
Auto-detects direction
Paste CSV or JSON and it converts to the other format.
Delimiter auto-detection
Handles comma, semicolon and tab-separated files.
Table preview
See the converted data as a table before downloading.
Handles quoted fields
Correctly parses commas and line breaks inside quoted CSV cells.
How to use it
- Paste your CSV or JSON data, or upload a file.
- The tool detects the format and converts automatically.
- Check the table preview for correct columns.
- Copy the result or download it as a file.
Worked example
Example
CSV: name,age\nAna,30\nBen,25
JSON: [{"name":"Ana","age":"30"},{"name":"Ben","age":"25"}]Who uses this tool
Developers
Convert exported spreadsheet data into JSON for an API or script.
Data analysts
Turn a JSON API response into CSV to open in Excel or Sheets.
No-code / automation builders
Reshape data between spreadsheet and JSON-based tools.
Tips for the best results
- Make sure your CSV has a header row — it becomes the JSON object keys.
- For JSON to CSV, use a flat array of objects with consistent keys for the cleanest result.
- Check for numbers vs text — CSV has no native number type, so all values come back as text unless you convert them after.
- Quote any CSV cell that itself contains a comma to avoid it being split into extra columns.
Common mistakes to avoid
- Converting JSON with deeply nested objects and expecting a clean flat CSV without checking the flattened column names.
- Mixing delimiters within one file, which breaks auto-detection.
- Forgetting a header row in source CSV, which causes generic Column1, Column2 keys instead of meaningful ones.
Why use AZRS QuickFix?
It is 100% free, needs no signup and has no watermark or usage limits. The tool runs in your browser, so what you type stays on your device, and it works on phones, tablets and desktops. New tools are added every week — bookmark this page or browse the full QuickFix toolbox.
Frequently asked questions
Is my data uploaded anywhere?
No, conversion happens entirely in your browser using JavaScript; nothing is sent to a server.
Does it handle commas inside quoted CSV fields?
Yes, standard CSV quoting with double quotes is parsed correctly, including embedded commas and line breaks.
What happens to nested JSON objects when converting to CSV?
They are flattened into dot-notation column names, for example address.city, so every value still fits into a flat spreadsheet cell.
Can I choose the CSV delimiter?
Yes, comma is the default but you can switch to semicolon or tab for regions or tools that expect those.
Are numbers preserved as numbers in JSON output?
Values that look like plain numbers are converted to JSON numbers automatically; anything with letters or leading zeros stays a string.
Is there a row limit?
No hard limit, but very large files may be slower since everything processes in your browser.