Boosting Audio Volume

Sometimes a video recording is too quiet. accurate adjustments can be made using the volume audio filter.

Increasing Volume by 50%

To increase volume by 50% (making it 1.5x louder):

ffmpeg -i input.mp4 -filter:a "volume=1.5" output.mp4

Using Decibels

You can also specify the gain in decibels (dB):

ffmpeg -i input.mp4 -filter:a "volume=5dB" output.mp4

Increasing volume too much can cause “clipping” (distortion). It is often safer to simplify normalize the audio rather than blindly boosting it.

Audio Normalization

To maximize volume without clipping:

ffmpeg -i input.mp4 -filter:a loudnorm output.mp4