JSON Key Mapper

Paste any JSON object below and instantly extract every key path - including nested objects and arrays. Free, browser-based, no login required.

How to Use JSON Keyper

1
Paste your JSON - copy any JSON object or API response and paste it into the left input box.
2
Click "Extract Keys" - JSON Keyper will recursively walk the entire structure.
3
View all key paths - every key path appears in the right box using dot notation (e.g. user.address.city) and bracket notation for arrays (e.g. items[0].name).
4
Copy or Clear - click Copy to send all keys to your clipboard, or Clear to reset both boxes.

Use Cases

API Exploration

Understand the structure of an unfamiliar API response at a glance without manually scrolling through hundreds of lines.

Data Transformation

Map source fields to destination fields in ETL pipelines, data migrations, and integration projects.

Schema Documentation

Generate a complete flat list of all fields in a JSON schema for sharing with your team or writing API docs.

Debugging

Quickly verify which fields are present in a JSON response when a parser isn't finding a field you expect.