Android
Turn Dial Pad Tones On or Off auf Android
Dial pad tones are the short beeps your phone plays each time you tap a digit on the dialing keypad. They exist purely for audio feedback so you can confirm a key press without looking at the screen, which helps when dialing by feel or entering long numbers such as conference call codes.
This sound is controlled independently from your ringtone, notification sound, and media volume. Muting your phone or switching to silent mode does not always mute the dial pad, which is why the tones can still surprise you in a quiet room even with the ringer off.
To change this behavior, go to Tap on Settings ➔ Tap on Sound & vibration ➔ Enable or disable Dial pad tones. Toggling this off removes only the keypad beep. Calls, ringtones, and notification sounds stay untouched.
If you actually want to silence calls or alerts and not just the dial pad, adjusting this setting will not help. In that case, use your phone's ringer volume or a focus/do not disturb mode instead, since dial pad tones and call audio are handled by separate controls.