Clean JSON Viewer — JSON Formatter & Beautifier

Pretty-prints, highlights and makes collapsible any JSON page. Open source, zero permissions, zero network, zero tracking.

Clean JSON Viewer turns any raw JSON page into a clean, readable, syntax-highlighted tree — automatically. Open a JSON endpoint, a *.json file or a REST response and it instantly formats and beautifies it: collapsible objects and arrays, color-coded keys and values, and clickable URLs. No button to press. WHAT IT DOES • Auto-formats and pretty-prints any page whose body is JSON — REST APIs, *.json files, even localhost dev servers. • Collapsible tree: fold and unfold objects and arrays, with item counts. • Syntax highlighting for keys, strings, numbers, booleans and null. URLs become clickable. • Toggle between Parsed and Raw views any time. • Automatic light and dark theme — follows your system setting. • Leaves every non-JSON page completely untouched. WHY CLEAN JSON VIEWER IS DIFFERENT • Open source and inspectable. • Zero permissions. It declares no Chrome permissions and no host permissions at all. • Zero network. It never makes a single request — your data is read and rendered locally and never sent anywhere. • No tracking, no adware, no account. It is a pure formatter: JSON in, readable tree out. The most popular JSON formatter went closed-source and started injecting adware and tracking while still claiming to be clean. Clean JSON Viewer is the honest alternative: it formats your JSON and does absolutely nothing else.