API Response Viewer
FreeVisualize and explore API JSON responses in a tree view
About API Response Viewer
A raw JSON response from a real API can be hundreds of lines of nested objects and arrays, and scrolling through it as plain text makes finding one field a chore. The API Response Viewer turns that wall of JSON into an explorable tree you can expand and collapse, so you can navigate deep structures and locate the exact value you care about.
Paste your JSON response and the tool renders it as a hierarchical tree with each object and array as a node you can open or close. There's nothing to install and no signup; it all happens in your browser, so even sensitive responses from internal services stay on your machine. It's a fast way to read, verify, and understand the data an API actually returned.
Common uses
- Expand a deeply nested response to confirm a value buried several levels down is present and correct.
- Collapse large arrays to focus on the top-level structure of an unfamiliar API's output.
- Verify the shape of a response matches the types your frontend code expects.
- Trace where a field lives in the hierarchy so you can write the correct access path in code.
- Inspect a sensitive internal API response without sending it through an external service.
How to use
- 1
Configure options
Set your preferences using the options panel below.
- 2
Click Generate
Click the process button to generate your result instantly.
- 3
Copy or download
Copy the result to clipboard or download it directly to your device.
Why ToolHub?
- Test APIs instantly
- No Postman needed
- Full header control
FAQ
Do I paste the JSON or fetch it live?
You paste the JSON response you've already received, and the tool renders it as an interactive tree for browsing.
Can it handle large responses?
Yes. Collapsible nodes let you manage big, deeply nested responses without losing track of the structure.
Is my JSON sent anywhere?
No. Parsing and rendering happen in your browser, so your response data stays local.
What if my JSON is invalid?
The tree relies on well-formed JSON, so malformed input won't parse. Fix syntax errors first, then paste it in.
Can I use API Response Viewer on mobile?
Yes — ToolHub is fully responsive and works on iPhone, Android, tablets and all modern browsers. No app install needed.