Adjust Video Volume

About Adjust Video Volume

This online video volume tool lets you increase, decrease, or mute audio (0% to 500% gain) or normalize loudness to a LUFS target directly in your browser. The video stream is copied losslessly when the format is unchanged, so only the audio is re-encoded. All processing happens locally for complete privacy.

What video formats are supported?

Input: MP4, WebM, MOV, and M4V (all of which preview in the browser). Output: keep the same format, or convert to MP4 (H.264 video, AAC audio), WebM (VP9 video, Opus audio), or MOV (H.264 / AAC). The audio codec is chosen automatically to be valid in the container you pick.

How do I adjust video volume?

Upload your video, choose an Audio Mode. In Gain mode use the slider or a preset (0% to 500%). In Normalize mode set a target LUFS. Then click 'Adjust Volume' to process. You can preview the result before downloading.

What is LUFS normalization and which target should I use?

LUFS (Loudness Units Full Scale) is the broadcast/streaming standard for perceived loudness, measured per EBU R128. Use -14 LUFS for YouTube, Spotify, and most streaming platforms, and -23 LUFS for EBU R128 / broadcast TV delivery. Normalize mode uses FFmpeg's loudnorm filter (loudnorm=I=target:TP=-1.5:LRA=11) so your deliverable hits the target instead of guessing percentages.

How does percentage gain relate to dB?

Gain in decibels is 20 x log10(multiplier). So 200% (x2) is about +6 dB, 50% (x0.5) is about -6 dB, 125% is about +1.9 dB, and 400% is about +12 dB. If you need exact loudness instead of a relative boost, use Normalize (LUFS) mode.

Does boosting the volume cause clipping, and how is it prevented?

Raw amplification above 100% can push peaks past 0 dBFS and clip, causing harsh distortion. In Gain mode this tool automatically adds a limiter (alimiter=limit=0.97) above 100% to catch those peaks, and Normalize/Peak modes use loudness control that is clip-safe by design. For the cleanest result on quiet sources, prefer LUFS normalization over a large manual boost.

What is the file size limit?

The maximum file size is 100MB. This ensures smooth processing in your browser. For larger videos, consider using desktop video editing software.

Can I increase volume above 100%?

Yes, up to 500% (5x the original, about +14 dB). A limiter is applied automatically above 100% to prevent clipping. For loud, professional results without distortion, LUFS normalization is usually a better choice than a large manual boost.

Will video quality be affected?

When you keep the same container format, the video stream is copied with no re-encoding, preserving 100% of the original visual quality, and faststart is added to MP4/MOV so playback can begin while streaming. Only when you convert containers (for example MP4 to WebM) is the video re-encoded. The audio is re-encoded (AAC for MP4/MOV, Opus for WebM) only when the volume actually changes; an unchanged 100% gain copies the audio losslessly.

What if my video has no audio track?

The tool detects videos with no audio and produces a valid output without an audio stream instead of failing. You will see a notice that no audio track was found.

Can I preview before downloading?

Yes! After processing, you can preview the video with adjusted volume to verify the result is what you want before downloading.

Is my video file safe?

Absolutely! All video processing happens directly in your browser using FFmpeg.wasm (WebAssembly). Your video file is never uploaded to any server. Everything stays private on your device.

Why does FFmpeg take time to load initially?

FFmpeg.wasm is a powerful video processing library (about 30MB) that runs in your browser. It only needs to load once per session. After loading, all volume adjustments will be fast and efficient.

How long does processing take?

Processing time depends on your video length and device performance. A typical 1-minute video takes 10-30 seconds. Longer videos or slower devices may take more time.