Convert between CSV and JSON without uploading anything
Spreadsheet data and structured data formats don't always play nicely together — a spreadsheet export needs to become JSON for an API or a script, or a JSON response needs to become a CSV that opens cleanly in a spreadsheet program. This tool converts either direction instantly, directly inside your browser, with nothing ever uploaded to a server.
How it works
- Pick a direction. Choose CSV → JSON or JSON → CSV.
- Paste your data or load a file. The output updates instantly as you type or edit.
- Copy or download the result. Grab the converted data directly, or save it as a file.
Common uses
- Converting a spreadsheet export into JSON for use in a script or an API request.
- Turning a JSON API response into a CSV that opens cleanly in Excel or Google Sheets.
- Reformatting exported data before importing it into a different tool or database.
- Quickly inspecting the structure of a CSV file by seeing it laid out as JSON.
Handling CSV formatting correctly
A common source of broken conversions is a CSV field that itself contains a comma — for example, an address like "123 Main St, Suite 4." Properly formatted CSV wraps such fields in quotes to avoid ambiguity, and this tool respects that formatting correctly, so those fields don't get mistakenly split into extra columns.
Your data stays private
Nothing you paste or load into this converter is sent anywhere — everything happens directly in your browser. See our Privacy Policy for full details.
A quick note on JSON structure
CSV is inherently flat — every value sits in a single row and column, with no nesting. JSON, on the other hand, can represent nested objects and arrays within a single record. When converting CSV to JSON, each row simply becomes an object with one property per column. When converting JSON back to CSV, any deeply nested structure would need to be flattened first — this tool works best with straightforward, flat JSON objects, which covers the large majority of everyday spreadsheet-style data, from contact lists to inventory records to survey results.
Frequently asked questions
+Is this CSV/JSON converter really free, with no sign up?
Yes. There's no account and no limit on how much data you can convert.
+Do you upload my data to a server?
No. The conversion happens directly inside your browser — nothing you paste or load is ever sent anywhere.
+Can I load a file instead of pasting text?
Yes — click "Load a file" to select a .csv or .json file from your device, and its contents will fill the input box automatically.
+How does the converter handle commas inside a CSV field?
Correctly — this tool follows standard CSV formatting rules, so a field containing a comma (wrapped in quotes, as proper CSV requires) won't be mistakenly split into extra columns.
+What happens if my JSON isn't a list of objects?
If you paste in a single JSON object rather than an array, it's automatically treated as a one-row table when converting to CSV.