A recording that came out too quiet is one of the easiest problems to fix and one of the most annoying to live with. This tool changes the level of an audio file or a video's soundtrack without touching anything else: the picture is stream-copied, so it stays bit for bit identical and the job runs quickly. Set the change in decibels the way an audio engineer would, as a plain multiplier if that reads more naturally, or hand the work to loudness normalisation, which measures the whole track and shifts it to a target in LUFS — the same approach streaming platforms use. A limiter is available so a hard boost does not square off the peaks.
Features
Works on video soundtracks and on standalone audio files
Change in decibels, as a multiplier, or as a percentage
Loudness normalisation to −14, −16, −23 or −11 LUFS targets
Optional limiter so a large boost cannot clip
Video stream is copied untouched, so the picture is unchanged
Output codec matched to the container: AAC, MP3, Opus, FLAC or PCM
Presets from half volume to four times, in one tap
Warns before a boost that would clip an already loud track
How to use the Audio Volume Changer
Drop in a video or audio file
Pick decibels, a multiplier, or loudness normalisation
Set the amount, or choose the platform target you are aiming for
Apply, then play the result back and download it
Example
Input
interview.mp4, +6 dB with clipping protection
Output
interview-volume.mp4 — audio 2× louder, video stream copied
Six decibels is a doubling of amplitude; the limiter catches the peaks that would have clipped.
Common errors & troubleshooting
The result sounds distorted after a big boost. — The track was already close to full scale, so the peaks clipped. Turn on the limiter, or use loudness normalisation, which raises the quiet parts without pushing the loud ones past the ceiling.
Nothing gets louder no matter what is entered. — The source may already be at maximum. A recording that peaks at 0 dBFS has no headroom left; normalisation with a limiter is the only way to make it seem louder.
The processing takes a while on a long video. — Only the audio is re-encoded, but the whole file still has to be read and written. A long recording takes proportionally longer because everything runs on your own machine.
The output plays with no sound at all. — Check the multiplier is not near zero, and that the source had an audio track to begin with. A screen recording made without audio permission has none.
Frequently asked questions
How many decibels is double the volume?
Six decibels doubles the amplitude, which is what a 2× multiplier does. Perceived loudness is a different question — most listeners describe about ten decibels as twice as loud.
What is loudness normalisation and when should I use it?
It measures the perceived loudness of the whole track and shifts it to a target, rather than applying a fixed gain. Use it when clips need to match each other, or when you are delivering to a platform with a published LUFS target.
What LUFS should a podcast be?
Around −16 LUFS for stereo is the usual podcast target, while YouTube and Spotify normalise to about −14 and broadcast in Europe works to −23. All four are offered here.
Does changing the volume re-encode the video?
No. Only the audio track is re-encoded; the video is stream-copied, so the picture is untouched and the file keeps its original quality.
Can I fix audio that is too loud rather than too quiet?
Yes — enter a negative decibel figure or a multiplier below one. Reducing level is lossless in the sense that nothing clips, though anything that was already distorted stays distorted.
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