Keycode Checker
Free online keycode checker tool, real-time detection
About Keycode Checker
Captures a keyboard event in the browser and shows the raw JavaScript properties plus cross-language key constants. Press any key while the dashed area is focused and the tool displays event.key, event.code, event.keyCode, event.which, location, and modifier state, then maps the key to constants for 13 languages and frameworks.
How to Use
1. Click the dashed capture area to focus it 2. Press any key (optionally with Ctrl/Shift/Alt/Meta) 3. The Key Details card shows the JavaScript event properties and the active modifiers 4. The Reference Table lists the matching constant name and numeric value per language 5. Press another key to refresh the table
Reference Table Coverage
Per-key output includes: JavaScript event.code and event.keyCode; C# (.NET) Keys.* names; Java AWT VK_* constants; C/C++ Win32 VK_* names and hex; Python pynput Key.* names; Go string literals; Rust winit KeyCode::*; C++ Qt::Key_*; X11/Xlib XK_*; GLFW GLFW_KEY_*; SDL2 SDL_SCANCODE_*; Android KEYCODE_*; Swift macOS carbonKeyCode; Flutter LogicalKeyboardKey.*. Not every key has an entry in every language.
▶Why does event.keyCode show 0 for some keys on modern browsers?
▶Are the Win32/Java/C# constants computed from the real key I pressed?
▶Does layout (QWERTY vs Dvorak) affect the result?
▶Can I capture keys while another input has focus?
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