JSON Visualiser support
Paste a payload, read it properly. Format, validate, explore, and type your JSON in the browser.
JSON Visualiser is an editor and tree viewer for the JSON you deal with every day. Paste an API response, a config file, or a log line, and it is validated as you type, formatted in one keystroke, and explorable as a collapsible tree. It turns escaped strings back into JSON, generates TypeScript types from any payload, and ships with a Chrome extension that opens raw JSON responses straight into the workspace. No account, no analytics, no server.
Frequently asked questions
Is my JSON uploaded anywhere?
No. The page is served as static files, and everything after that, parsing, validation, the tree view, and type generation, happens in your browser. Your documents are saved in your browser's IndexedDB.
Does it work offline?
Yes. JSON Visualiser installs as a progressive web app and caches itself, so once it has loaded you can open it and keep working without a connection.
Why is the Tree View missing?
The Tree View only appears when the document is valid JSON. Fix the error the editor underlines and the tab comes back.
What does Unescape do?
It replaces JSON escape sequences, such as backslash n, backslash t, and escaped quotes and backslashes, with the characters they stand for. It is meant for JSON that was stringified twice, which is common in logs and message queues.
Which languages can Generate Types produce?
TypeScript interfaces. Nested objects become their own named interfaces, and arrays are typed from their items.
How do I use the Chrome extension?
Install JSON Visualiser from the Chrome Web Store. When you land on a raw JSON response, send it to the workspace and it opens formatted, with the source URL kept alongside the document.
Can I have more than one document open?
Yes. Every browser tab keeps its own document, so you can compare two payloads side by side in two tabs without one overwriting the other.
Permissions
- None for the web app. It asks for no camera, microphone, location, notifications, or file system access.
- The Chrome extension reads the JSON on the page you choose to send, so it can open it in the workspace.
Requirements
- A modern browser. Chrome, Edge, Firefox, and Safari all work.
- Chrome, for the browser extension.
Privacy
- Parsing, validation, formatting, and type generation all run in your browser.
- Your workspace is saved in the browser's IndexedDB, one document per tab.
- No account, no sign-up, no analytics, and no server that receives your JSON.
- Workspace state for closed tabs is cleaned up automatically.
Get in touch
Still stuck? Email and you'll get a real reply from a real person, usually within a day.