Guide: inspect, format, and validate JSON
API logs and `.json` files often arrive minified or inconsistently indented. The viewer renders nested objects and arrays as a tree, pinpoints syntax errors by line, and toggles between compact and pretty layouts.
Parsing happens locally in your browser — suitable for staging payloads or sanitized dumps. Nothing is sent to WebDevTools servers, which helps when inspecting masked tokens or client data in a controlled environment.
Use it before JSON→TypeScript conversion, when reviewing webhooks, or when you need a subtree without selecting the whole file. Large trees are easier with collapsed nodes and key search when available.
Step by step
- Paste or import JSON — Paste raw output from the network tab or an exported file. Trailing commas, quotes, or invalid comments are flagged with position.
- Pick format or minify — Pretty-print for humans or minify to compare payload size across requests.
- Walk the tree — Expand nested nodes, copy single values, and confirm types (string, number, boolean, null) per key.
- Export what you need — Copy corrected JSON into test fixtures, docs, or the JSON→TypeScript tool.