JSON to CSV (Nested)

Nested JSON to CSV conversion is the process of taking complex, hierarchical JSON data with nested objects and arrays and flattening it into a flat, tabular CSV format. While flat JSON arrays convert trivially to CSV, deeply nested structures require a strategy to represent each nested field as a column with a dot-notation key (e.g., address.city, address.zip).

This is particularly useful when you need to import hierarchical API responses into spreadsheet applications like Excel or Google Sheets, load data into relational databases, or share structured data with non-technical stakeholders who need a simple row-and-column view. Data analysts, backend developers, and ETL pipeline engineers commonly use this conversion for data migration, reporting, and integration tasks.

The tool automatically detects nested objects and arrays in your JSON, flattens object keys using dot notation, and expands array fields into separate rows. Empty values are handled gracefully, and you can customize the CSV delimiter and quoting behavior to match your target system's requirements.

1. Paste JSON — Enter a JSON array of objects with nested data into the input textarea. You can use the Load Sample button to try with example data.
2. Configure options — Choose your CSV delimiter (comma, semicolon, or tab), toggle Quote all fields to wrap every value in quotes, and enable Include empty columns to keep columns for fields that may be missing in some objects.
3. Generate CSV — The output table appears automatically. Review the row and column counts displayed above the output.
4. Copy the result — Click Copy CSV to copy the flattened data to your clipboard, then paste it into Excel, Google Sheets, or any CSV-compatible application.