JSON Key Extractor

A JSON key extractor parses a JSON document and collects every key that appears in the structure. It outputs a flat list of key names, nested paths in dot notation, key count, and depth information. This is useful for understanding API response structure, documenting data schemas, generating TypeScript interfaces, and validating that expected keys are present.

When working with APIs, you often need to know what fields are available. Instead of manually scanning nested JSON, this tool extracts all keys and paths in one go. You can filter by depth, sort alphabetically, and copy the result for use elsewhere.

Paste your JSON into the input area. The tool parses it and extracts keys. Toggle 'Include array indices' to show or hide paths like arr.0, arr.1. Use 'Sort alphabetically' to order the output. Filter by depth to focus on a specific nesting level (0 = root, 1 = first level, etc.).

View the flat key list and nested paths. Use 'Copy keys' to copy the result to your clipboard. The key count and max depth help you understand the structure's complexity.

API responses are often deeply nested. This tool helps you quickly see all available fields without manually expanding the JSON. Use nested paths to understand relationships: user.profile.avatar indicates a three-level structure. Filter by depth to see only top-level keys (user, posts, meta) or drill into specific branches. The output is useful for documentation, testing, and code generation.