Firefox:DevTools
lastmod 2026-11-10created 2023-09-012 edits
Firefox DevTools are the web developer tools built into Firefox. They provide an element inspector, console, JavaScript debugger, network monitor, performance profiler, storage inspector, and more, with especially well-developed CSS grid and flexbox inspectors and an accessibility inspector. They open with F12 or Ctrl+Shift+I, and Firefox for Android can also be inspected through remote debugging.