What JSON input format is required?

The input must be a JSON array of objects. All objects should share the same keys, though missing keys in some rows are allowed and output as empty cells.

How are nested objects handled?

Nested objects are flattened using dot notation. For example, {"address": {"city": "London"}} becomes a column named address.city.

Is my data safe to convert here?

Yes. All conversion happens in your browser. No data is transmitted to any server.

JSON → CSV Converter

Delimiter

JSON Input

CSV Output

Why use a private JSON to CSV converter?

Converting JSON to CSV often involves pasting sensitive API payloads or database records into an online tool. formatvault converts your data entirely in your browser — no data is uploaded, logged, or transmitted to any server.

How it works

The converter flattens the JSON array of objects into tabular form. Nested objects are dot-notation flattened (e.g. address.city) so every value fits a CSV column. You can choose the output delimiter: comma, tab, pipe, or semicolon.

Common use cases

Exporting API response data to CSV for import into Excel or Google Sheets
Converting database query results (JSON) to CSV for reporting tools
Preparing data for upload to Salesforce, HubSpot, or other CRMs
Flattening nested API payloads for analysis in pandas or R
Converting JSON logs to CSV for filtering in spreadsheet software

Frequently asked questions

What JSON input format is required?: The input must be a JSON array of objects. All objects should share the same keys, though missing keys in some rows are allowed and output as empty cells.
How are nested objects handled?: Nested objects are flattened using dot notation. For example, {"address": {"city": "London"}} becomes a column named address.city.
Is my data safe to convert here?: Yes. All conversion happens in your browser. No data is transmitted to any server.