The JSONForge Browser Extension

What the extension does

When you land on a page serving JSON (a raw API response, a JSON file, or content-type application/json), the extension detects it and renders it with the same formatter and tree viewer as the website: collapsible, syntax-highlighted, and validated. You get a document you can explore in place of a wall of unformatted text.

The popup works the other way around. Paste any JSON snippet into it and format it there without leaving what you're doing. Use it when the JSON sits in your clipboard instead of on a page.

Installing it

The extension runs on Chromium-based browsers (Chrome, Edge, Brave, Arc, Opera) and installs from the Chrome Web Store. The 'Get the extension' button in this site's header links to the listing. Click 'Add to Chrome' and it works right away, with no account, no setup, and no permissions beyond reading the JSON pages you open.

It formats locally from the moment you install it. Open any raw JSON endpoint, such as the public JSONPlaceholder API, and the extension shows its formatted view before the browser's default plain-text rendering takes over.

A typical debugging workflow

Open the endpoint you're debugging in a tab (or via the Network panel's 'open in new tab'), and the extension renders the response as a collapsible tree. Collapse everything, expand the branch you're investigating, and use search to jump to a key anywhere in the document. Switch to the raw view when you need to copy the exact bytes for a bug report.

The extension uses the same engine as the website's tree viewer, so what you see in the tab matches what you'll get if you later paste the payload into any JSONForge tool. Moving from reading to converting or validating brings no surprises.

Extension vs. website

Reach for the extension when you're reading live API responses in the browser and want them readable without a context switch. Use the website for heavier work like conversions (YAML, CSV, TypeScript), schema validation, repair, and the placeholder API, since the full toolkit lives there. Both share one engine, so results match.

Privacy

The extension processes JSON locally in your tab and transmits nothing: no analytics, no telemetry, and no page content leaves the browser. Its content script checks whether the page you opened is a raw JSON response and stops there if it isn't. It reads the clipboard only when you click 'Paste' in the popup. The site's privacy policy documents this behavior in detail.