CurlyJSON – JSON Viewer & Formatter

View API responses as a tree: format, copy paths, spot API keys before sharing. Private: no tracking, no network requests.

Turn raw JSON into something you can actually read. CurlyJSON transforms API responses into clean, interactive, easy-to-navigate JSON, right in your browser. Open any API URL and instantly explore the response in three ways: an interactive tree, beautifully formatted JSON, or raw text. Built for speed, simplicity, and privacy. 🚀 Fast, even with large files - Open a 10 MB JSON response in about 2 seconds, with support for files up to 50 MB. - Navigate complex JSON with a collapsible, interactive tree. - Search keys and values instantly, even inside collapsed nodes (press / or Ctrl+F). 🔎 Explore JSON effortlessly - Click any value to copy its JSON path (e.g. $.items[2].price) or the value itself. - Open URLs directly from your JSON data. - Download responses as JSON files with one click. - Large integers stay exact: no rounding of 64-bit IDs. 🔐 Sensitive data protection - Automatically detects likely API keys, access tokens, and passwords. - Mask sensitive values with a single click. - Get a warning before sending JSON that contains secrets anywhere. ⚡ Works where other formatters struggle - Handles pages with strict Content Security Policies (CSP). - Supports JSON served as plain text and newline-delimited JSON (NDJSON). - Light and dark themes that follow your system setting. - Keyboard shortcuts: 1, 2, 3 to switch views; / to search. 🛠️ More than a JSON viewer Need advanced tools? Click "Open in CurlyJSON" to continue on curlyjson.com, with JSON Diff, jq queries, JSON Schema validation, code generators, and data converters. 🔒 Privacy isn't a feature. It's the foundation. - No tracking. No analytics. No ads. - The extension makes no network requests. - Your JSON stays entirely in your browser. - No website access required at installation. - Format only the pages you choose. Optional automatic formatting asks for your permission first. 100% free. No sign-up. No compromises. Built by the team behind https://curlyjson.com Your JSON. Your browser. Your control.