JSON Flatten

Convert nested JSON objects and arrays into a flat key-value map with dot and bracket notation. Paste JSON and click Run.

Runs entirely in your browser
No data stored or sent to a server
Free forever — no signup
Instant conversion

Input and Output

Use the interactive encoder and decoder on this page to process your text.

Learn more about flattening JSON

How to Flatten Nested JSON

JSON Flattening

When to Flatten JSON

Flatten nested objects for CSV export, spreadsheet imports, log indexing, and flat key-value storage.

Frequently asked questions

How are nested keys represented?

Object keys use dot notation (user.name) and array indices use brackets (items[0].id).