BearerPeek

BearerPeek is a Chrome extension that allows you to decode and inspect JSON Web Tokens (JWT) directly in your browser. It’s ideal for developers, security professionals, and anyone who needs to analyze token data quickly and securely. The tool provides an intuitive interface where you can paste any JWT and instantly see the decoded header, payload, and signature in syntax-highlighted JSON format. Key features include a clear algorithm badge showing the signing method (like HS256 or RS256), a signature presence indicator for unsigned tokens, and copy buttons for every section. The extension also tracks expiry with a live countdown timer and clearly flags expired tokens. It runs five automatic security checks on each token to ensure it meets common standards, such as having an expiration claim and not using the 'none' algorithm. BearerPeek automatically scans web pages for JWT-shaped strings in text, input fields, meta tags, and inline scripts. A badge appears in the Chrome toolbar when tokens are found, and a popup lets you navigate through multiple detected tokens. For added convenience, it offers full-tab mode to pop out the inspector into a separate tab and supports both dark and light themes. Your privacy is a top priority with BearerPeek. All processing occurs locally within your browser using the Web Crypto API, ensuring no data is sent to servers or stored beyond your current session. This makes it safe for use in any environment where data security is critical. Try BearerPeek today and enhance your workflow. If you find value in this tool, consider supporting its development through GitHub Sponsors.