Header Grep

Header Grep adds a dedicated panel to Chrome DevTools for searching HTTP request and response headers with regular expressions. Whether you are verifying caching rules, tracking down a CORS issue or checking security headers, Header Grep shows you every matching header across all requests on the page, in one place. FEATURES • Regex search on header names and values, filtering as you type with matches highlighted • Search request headers, response headers or both, with an optional case-sensitive mode • Group results by header to see which requests share a value, or by request to see every matching header per URL • Method, status code, resource type and timing for each request • One-click copy of headers and URLs • Includes requests made before the panel was opened • Preserve log keeps results across page navigations • Save frequently used filters and reapply them in one click • Native DevTools look that follows your light or dark theme HOW TO USE 1. Open Chrome DevTools (F12, or Cmd+Option+I on macOS) 2. Select the "Header Grep" tab 3. Enter a regular expression for the header name, the value or both PRIVACY Header Grep only reads network data that DevTools already displays. Nothing is collected or sent anywhere, and your settings and saved filters are stored locally in your browser. Header Grep is open source: https://github.com/byrdal/header-grep