DevTools Detect

DevTools Detect is a browser-focused JavaScript package for estimating whether a browser's developer tools are currently open. It also reports whether detected DevTools are positioned vertically or horizontally. Applications can inspect the current state directly or listen for a custom event when the state changes. The package supports Chrome, Safari, Firefox, and Opera developer tools. It can be used for interface behaviors such as pausing graphics or displaying additional debugging information while tools are open. However, browser changes have made detection unreliable, and the project explicitly warns about false positives and limitations with undocked tools. The repository was archived in May 2026 and is now read-only.