JSON CSV Converter

How it works

For JSON to CSV, the tool collects the union of keys across all objects to build a header row, then writes one row per object with proper CSV quoting. For CSV to JSON, it parses the CSV respecting quoted fields and infers numbers and booleans from plain text cells.

Benefits

• Bidirectional conversion between JSON arrays and CSV
• Correct CSV quoting for commas, quotes, and newlines
• Automatic type inference when converting CSV back to JSON
• Handles objects with missing or extra keys gracefully

Use cases

• Export API JSON responses to CSV for spreadsheets
• Import CSV exports from spreadsheets into JSON for scripts
• Convert test fixtures between JSON and CSV formats
• Clean up data before loading it into another tool or database

Best practices

• Confirm your JSON is an array of objects before converting to CSV
• Review the header row after conversion to ensure key names are as expected
• Watch for stray quotes in source data before pasting as CSV
• Validate numeric-looking strings you want to keep as text (like IDs) separately

Common mistakes

• Pasting a single JSON object instead of an array of objects
• Assuming CSV preserves nested objects or arrays (it does not—flatten first)
• Forgetting that different row keys produce empty CSV cells, not errors
• Not checking whether numeric-looking IDs should stay as strings

Privacy

All parsing and conversion logic runs locally in your browser. ToolHub never receives the JSON or CSV you paste unless you separately opt in to on-device history.