Change the volume of a video
Drop a video and set its sound: louder, quieter, levelled to a peak, faded in and out, or removed. The picture is copied as it is, only the sound is re-encoded, and the panel warns you before a boost would distort.
Updated November 5, 2026
Options
The picture is copied as it is; only the sound is re-encoded.
How it works
- Drop a video with sound anywhere on this page.
- Choose a gain in dB or percent, normalize, or remove the sound; add a fade if you like.
- Download the video (longer clips: press Change video volume first): the picture untouched, the sound changed.
What people come here for
A phone video of a talk that is too quiet to hear. A concert clip that distorts on every chorus. A screen recording with a loud notification that needs levelling before it goes into a presentation. A clip whose music you cannot use and want to post silent. Drop the video, choose a gain from −30 to +30 dB, Normalize to a peak, or Remove the sound, and the peak line shows where the loudest moment will land.
Because the picture is never re-encoded, the result is ready in a fraction of the time a full re-encode would take, and it looks exactly like the original.
Normalize, gain and fades
Gain is a fixed lift or cut: +6 dB, the default, is clearly louder without being harsh on most phone recordings. Normalize is for files whose loudest point you do not know: it measures the peak and scales everything so that peak sits at −1 dBFS. Fade in and Fade out, up to 10 seconds, soften the start and the end, useful when the clip was trimmed in the middle of a sentence or a song.
Formats, batches and phones
MP4, MOV, M4V, WebM and MKV are accepted, up to 2 GB each and 5 at a time with the same setting. Keep the format as it is, or choose MP4 so the clip plays on every phone and in every chat app. The sound is decoded, changed and encoded on your device, in the browser; the video never leaves it.
Why people use it
Free, no account
Every tool is free, with no sign-up, no e-mail address and no limit on how often you use it.
Your files stay on your device
The browser opens the file and processes it in memory, on your device. Nothing is uploaded, so nothing can be kept, leaked or looked at.
No watermark
The result is yours as it is: no watermark, no branding, no trial version.
Any device
A phone, a tablet or a computer with a current browser is enough: no app to install, no software to update.
Works offline after the first visit
The browser keeps the pages and their engines, so a tool you have opened once keeps working without a connection.
Open-source engines
The code that does the work is open-source software, named on the Licences page, running as WebAssembly in your browser.
Why it is private
Everything you type or drop here is handled by your browser, on your device. Nothing is uploaded. To verify, open your browser's developer tools, go to the Network tab, and use the tool: you will see no request carrying your data.
While a file is being processed, the counter under the result shows the page's network traffic: 0 requests and 0 B for your data.
How to check it yourself, step by step
What you can check yourself
Open your browser's developer tools on the Network tab before you drop a file: while the tool works you will see no request carrying your data, and the counter under every result shows the page's own measurement.
The site sets no cookies, so there is no cookie banner. Anonymous usage counts and error reports without file names are the only things that leave the page, as the privacy policy describes.
Every change goes through thousands of automated tests in three browser engines, including a guard that fails a test if a single byte of a file leaves the page.
Frequently asked questions
- Does it re-encode the video?
- No. The picture is copied packet for packet, so it keeps its quality and the job is fast. Only the sound is decoded, changed and encoded again: AAC in MP4 (Opus where the browser has no AAC encoder, as in Firefox), Opus in WebM, at a bitrate that follows the original's.
- dB or percent?
- Both say the same thing: +6 dB is about 200 %, −6 dB about 50 %. The percent is the size of the waveform, not how loud it feels; for a clearly louder result, +6 to +10 dB is a good start.
- Why does it warn about clipping?
- Sound has a ceiling. If the loudest part is already near it, a boost pushes it over and those peaks are cut flat, which sounds harsh. The panel measures the loudest sample first and tells you the largest gain that stays clean; Normalize lifts the whole track exactly up to the ceiling instead.
- What does Normalize do?
- It finds the loudest sample of the sound and scales everything so that peak lands on the level you choose (−1 dBFS by default). It matches peaks, not perceived loudness (LUFS), and it raises a very quiet track by 20 dB at most so hiss is not blown up.
- What happens when I remove the sound?
- The sound track is left out and the picture is copied as it is, so the file gets a little smaller. A video with no sound track at all is refused with a clear message: there is no volume to change.
- Can I make several videos equally loud?
- Choose Normalize with the same peak level and up to 5 videos in one list: each one ends with its loudest moment at that level. It matches peaks, not perceived loudness, so a clip with a single bang may still sound quieter than the others.
- Does the file size change?
- Hardly. The picture is copied as it is and the new sound track is about the size of the old one. With Remove the sound the file gets a little smaller.
- Does it work on an iPhone video or on a phone in general?
- Yes. MOV files from an iPhone are accepted, and the tool runs in the phone's browser with nothing to install. The result plays on the phone and anywhere else.
- Can I add music instead of changing the volume?
- Not here. Add audio to video puts a song or a voice-over on the clip, replacing or mixed with its sound; it also lets you lower the original under the music.
- Can I change the volume of only one part of the video?
- No, the gain applies to the whole clip. Cut the part out with Trim video, change its volume here, and join the pieces again with Merge videos.
Install it as an app
Chrome, Edge and Android browsers offer to install this site from the address bar or the menu; on iPhone use Share, then Add to Home Screen. It opens like an app, keeps working offline and still processes everything on your device.