Convert JSON to CSV – API data to spreadsheet

JSON (JavaScript Object Notation) stores data as structured objects with key-value pairs. CSV (Comma-Separated Values) organizes data in a flat table format with rows and columns. The converter flattens JSON objects into tabular rows, using property names as column headers.

For an array of JSON objects, each object becomes one row in the CSV output. The converter extracts all unique keys from the JSON data and uses them as column headers in the first row. Values are then placed in the corresponding columns for each record.

The resulting CSV uses standard formatting with comma delimiters and proper quoting for values that contain commas, quotes, or newlines. The conversion runs entirely in your browser — no data is sent to any server.

CSV is a flat tabular format — it cannot natively represent nested objects or arrays. The converter handles nesting in several ways:

• Nested objects – flattened using dot notation. {"address": {"city": "Warsaw"}} becomes a column called address.city.
• Arrays of primitives – serialized as comma-separated strings within a single cell.
• Arrays of objects – serialized as JSON strings within the cell, preserving the structure for manual parsing.
• Null values – converted to empty cells in CSV.

For best results, use JSON with a flat structure (array of objects with primitive values). Deeply nested JSON may produce many columns with dot-notation headers.