Increase Video Volume Online — Make MP4 Louder, Quieter or Mute

Raise, lower or mute a video audio track without touching its picture, from silence to four times the original level.

A recording that came out too quiet to hear, or so loud it distorts on a phone speaker, is fixable without opening an editor. Set a level anywhere from silence to four times the original, or tick Mute to silence it entirely; only the soundtrack changes, while the picture is re-encoded without any visual edits.

How to make a video louder

  1. Drop an MP4, MOV or M4V file onto the upload zone to load it.
  2. Drag the Volume slider anywhere from 0% to 400%, type an exact percentage, or tick Mute for a silent track.
  3. Click Export MP4 and download the volume-<your clip>.mp4 file once the progress reaches 100%.
  4. Play the result; if loud passages sound harsh or crackly, lower the percentage and export again.

Video volume percent to decibels

The percentage multiplies the waveform's amplitude, and the decibel change is 20 × log10 of that factor. Perceived loudness grows more slowly than amplitude, so 200% sounds clearly louder but not twice as loud.

Gain is applied to decoded samples

The soundtrack is decoded to raw samples, each one multiplied by the factor you set, then compressed again as AAC and muxed back alongside the re-encoded picture. That is a genuine change to the recorded waveform, not a playback hint, so the file is louder or quieter everywhere it is played.

A setting of one hundred per cent is the identity: the level is unchanged. Below that the waveform is scaled down, which is always safe. Above it the waveform is scaled up, which is safe only while there is headroom left.

Why boosting can distort, and what happens when it does

Digital audio has a hard ceiling. Multiplying a sample past it has to go somewhere, and the two options are wrapping — which turns a loud passage into harsh noise — or clamping, which flattens the peak. This tool clamps, so an over-boosted file sounds compressed and slightly harsh rather than destroyed.

The practical consequence is that a quiet recording has plenty of room to be lifted, while one that was already near the ceiling has almost none. If a boost sounds unpleasant, lower the percentage and export again rather than accepting the flattened peaks.

Muting as a first-class option

Ticking Mute sets the level to zero and disables the slider, producing a file with a genuinely silent track rather than one that merely has its volume turned down. That is the right output when you intend to lay a music bed or a voice-over over the footage elsewhere.

Because the result still contains a valid audio track, editors and upload pipelines that expect one will not complain the way they sometimes do about a file with no track at all.

Video volume formats, output and free limit

The soundtrack is boosted in your browser

Decoding, scaling and re-encoding the audio all run in this tab, and the rebuilt MP4 goes straight to your downloads. Nothing is uploaded, so a private recording never passes through someone else's server on its way to being louder.

Questions people ask about Video Volume Changer

Can this rescue a recording where the microphone barely picked anything up?
Partly. Amplifying raises the quiet voice but raises the hiss and room noise by exactly the same amount, since the tool has no way to tell them apart. It helps a usable-but-quiet recording and cannot save one that captured almost nothing.
Is the picture re-encoded too?
Yes, because the file is rebuilt to carry the new soundtrack. The frames are compressed again at a generous bitrate, so there is a small quality cost that is not normally visible but is worth knowing about before repeated round trips.
What does four hundred per cent actually mean?
Each sample is multiplied by four, which is roughly a twelve-decibel lift. On most material that is far more than needed and will clip; it exists for genuinely faint recordings where a smaller boost leaves the result still inaudible.
Can I change the level of just one part of the clip?
Not here — the factor applies uniformly across the whole file. Adjusting a specific passage, fading in or out, or balancing several sources against each other is timeline work, which the Audio Studio's track editor is built for.
Can I lower the volume of a video instead?
Yes. Any value under 100% scales the soundtrack down, and lowering is always clean because samples cannot be pushed past the ceiling. 50% is about 6 dB quieter, and 0% or the Mute box gives a completely silent track.
Is this the same as normalizing the audio?
No. This page multiplies every sample by the one factor you choose, whatever the source level. Normalizing measures the loudest peak and sets the gain for you; Change Audio Volume has a Normalize peak mode, but it works on audio files and will not put the result back into your video.
Can I save the louder video in another format?
No, the export is MP4 only, with H.264 picture and AAC sound. If you need just the boosted soundtrack, load the finished MP4 into the Audio Extractor, which can save it as MP3, WAV, FLAC, AAC or Opus.
Which video formats can I boost?
MP4, MOV and M4V. Files in WebM, AVI or MKV containers cannot be opened by the MP4 demuxer this page uses, so convert them before boosting. A clip without a decodable audio track exports as picture only, since there is nothing to amplify.
How do I make a video louder on my iPhone?
Open this page in your phone's browser and follow the same steps, provided it supports WebCodecs. The page checks for the video encoder on load, but audio encoding is a separate feature, and without it the export has no soundtrack, so play the file back. We have not tested specific iPhone models.

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Content reviewed 2026-09-27.