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All keys and keycodes available in JavaScript

3 min read
Published on 22nd March 2024

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Creating a comprehensive and up-to-date list of all possible key values and their corresponding keycodes in JavaScript presents a challenge due to modern browser standards moving away from keyCode properties in favor of event.key. The use of keyCode is deprecated, as it does not provide a reliable cross-platform or cross-browser way of identifying key actions, especially considering internationalization and accessibility. The event.key property is now recommended for identifying keys because it is more readable and less dependent on the physical keyboard layout.

Below is a reference of some commonly used key values alongside their traditional keyCode values, keeping in mind that you should prioritize using event.key in new projects.

Understanding event.key over keyCode

  • event.key provides the value of the key pressed, making it easier to understand and maintain code. For example, pressing the A key will yield "a" or "A" depending on whether the shift key is also pressed.
  • keyCode, a numerical value, is deprecated and may not be supported in future web standards. It offered less readability and was more challenging to use without referencing a list of codes.

Common Key Values and Their keyCode

Below is a list combining both event.key values for modern development practices and their corresponding (but deprecated) keyCode values for reference:

Alphanumeric Keys

  • A-Z: event.key is "a" to "z" (lowercase without shift key, uppercase with shift key), keyCode is 65 to 90
  • 0-9: event.key is "0" to "9", keyCode is 48 to 57 for top row numbers

Special Characters (vary by keyboard layout)

  • Space: event.key is " ", keyCode is 32
  • Enter: event.key is "Enter", keyCode is 13
  • Escape: event.key is "Escape", keyCode is 27

Control Keys

  • Shift: event.key is "Shift", keyCode is 16
  • Control (Ctrl): event.key is "Control", keyCode is 17
  • Alt: event.key is "Alt", keyCode is 18
  • Backspace: event.key is "Backspace", keyCode is 8
  • Tab: event.key is "Tab", keyCode is 9

Arrow Keys

  • Left: event.key is "ArrowLeft", keyCode is 37
  • Up: event.key is "ArrowUp", keyCode is 38
  • Right: event.key is "ArrowRight", keyCode is 39
  • Down: event.key is "ArrowDown", keyCode is 40

Function Keys

  • F1-F12: event.key is "F1" to "F12", keyCode is 112 to 123

Detecting Key Actions

When detecting key presses, rely on event.key:

document.addEventListener('keydown', (event) => {
    console.log(`Key pressed: ${event.key}`);
});

Why Move Away from keyCode

The movement away from keyCode towards event.key was motivated by several factors:

  • Readability: event.key is much more understandable without referring to documentation.
  • Internationalization: event.key is less dependent on the physical location of keys, making it more suitable for international applications.
  • Deprecation and Future Support: Modern web standards recommend against using keyCode, as it may not be supported in future browsers and devices.

Conclusion

While historical keyCode values are part of JavaScript's legacy in handling keyboard events, modern web development practices encourage the use of event.key for a more readable, reliable, and future-proof approach. Transitioning to event.key not only aligns with current web standards but also enhances the accessibility and internationalization of web projects. Remember, the key to successful keyboard event handling is understanding user needs and browser compatibility to create inclusive and functional web applications.