JSON Flattener

Flattening JSON converts a deeply nested object into a single-level object where each key represents the full path using dot notation. For example, {"a":{"b":1}} becomes {"a.b":1}. This is useful for database storage, CSV export, and data analysis.

Dot notation joins parent and child keys with periods. Nested objects use dots (e.g., "user.address.city") and array elements use bracket indices (e.g., "items.0.name"). This creates a flat key-value structure that is easy to query and process.

Yes. This tool supports both flattening and unflattening. Toggle the mode to convert dot-notation keys back into a properly nested JSON object, reconstructing the original hierarchy from the flat key paths.

Yes! All processing happens entirely in your browser. Your JSON data is never sent to any server. No data is collected, stored, or transmitted.

This tool handles objects, arrays, nested objects within arrays, and deeply nested structures of any depth. Primitive values like strings, numbers, booleans, and null are preserved as leaf values in the flattened output.