About the JSON Key Extractor Online Free Tool

The JSON Key Extractor Online Free Tool reads a JSON object or array and lists the paths it finds, including nested object keys and optional array indexes. It is useful for auditing payload shape, building field maps, and checking what keys appear in API responses.

Extraction runs locally in your browser. The tool parses the JSON you paste, walks the structure up to the selected depth, and reports paths in the order or sort mode you choose.

How to Extract JSON Keys Online

1. Paste valid JSON into JSON input.
2. Choose whether paths should be unique and whether array indexes should be included.
3. Set a Max depth when you want to stop traversal after a certain nesting level.
4. Choose the output sort mode.
5. Click Extract Keys and copy the resulting path list.

Choosing Options Correctly

Unique keys only:
Leave this on when you want one copy of each path. Turn it off when repeated paths are meaningful for your review.

Include array indexes:
Leave this off for reusable path maps such as users[].name. Turn it on when exact positions like users[0].name matter.

Common Use Cases

• Auditing API response fields.
• Preparing JSON-to-CSV mapping notes.
• Checking whether nested keys exist in sample data.
• Comparing payload structure before writing validation rules.

Quick FAQ

Why did extraction fail?
The input may not be valid JSON, or it may contain a top-level value the extractor does not expect.

Does this validate field types?
No. It extracts key paths; it does not prove that values match a schema or API contract.

Can I paste sensitive JSON here?
Avoid pasting secrets, tokens, or customer data unless your workflow allows it.

What do array indexes mean?
Indexes show where keys appear inside arrays. Disable them when you want generalized paths instead of item-specific paths.