This tag is used for posts that contain audio content of any kind, including music, sound effects, and voice acting.

Note that this tag applies only to Flash- or WebM-based posts, as these are the only formats supported by e621 that can carry audio.

See also:

• ai_generated_audio - Posts featuring audio that has been partially or wholly AI generated. Usage of this tag upon upload is mandatory if a post contains AI assisted or generated audio.
• audio_sampling - Posts that primarily feature sampled audio from commercial sources such as video games.
• music
• music_video - An animation created for the purpose of showcasing a musical piece.
• music_only - Animations with a music track, but no sound effects.
• synced_to_music - Animations that are synchronized to a music track. Not always music videos.
• no_sound - The opposite of sound, i.e. silence.
• sound_warning - A warning tag to indicate the presence of loud sounds in a post, usually at the very beginning.

• voice_acted - Posts featuring voiced dialogue or other vocal sound effects. Voice actors may be credited in the description of a post.
• chinese_audio
• english_audio
• finnish_audio
• french_audio
• german_audio
• japanese_audio
• korean_audio
• polish_audio
• russian_audio

• sound_effects: mainly used for written sound effects including approximated sounds (examples: bzzzt, kerploosh)
• onomatopoeia: Any word in a picture that serves as a sound effect. onomatopoeias use actual words to describe the sound (examples: boom, buzz)