No. ffmpeg.wasm runs inside your browser; audio never leaves your device.

Adding +6 dB causes distortion — why?

Positive gain pushes peaks above 0 dBFS and clips, unless the source had headroom. Cutting (-3 to -6 dB) is the safe direction. Boosting cleanly requires a limiter / mastering chain, which this tool does not include.

How are dB and multiplier related?

multiplier = 10^(dB/20). +6 dB ≈ 2x, +12 dB ≈ 4x, -6 dB ≈ 0.5x, -20 dB ≈ 0.1x. Useful rule of thumb: 'double the level' is roughly +6 dB.

Same output format as input?

Same extension. The volume filter requires re-encoding, so the codec is re-encoded with ffmpeg defaults (mp3 → libmp3lame, wav → pcm_s16le, aac → aac, ogg → libvorbis, etc.). Bitrate is left to ffmpeg's defaults.

Same gain for every file?

Yes — the single slider value is applied to all dropped files. If you need per-file gains, run the tool once per file.

Back to Audio

Audio volume — adjust by dB or linear multiplier

Adjust the loudness of audio files in bulk via ffmpeg.wasm's volume filter. Use the dB slider (-30 to +30 dB) or the linear multiplier (×0.03 to ×31.6). +6 dB ≈ 2x, -6 dB ≈ half. To avoid clipping, try negative values first and compare. Supports batch processing and a single ZIP download. Runs entirely in your browser — audio never leaves your device.

audio

How to use

Drop audio files. Use the center dB slider (-30 to +30 dB) or the linear multiplier text (×0.03 to ×31.6) to dial in the gain, then click Apply. ffmpeg.wasm's `volume` filter applies the same gain to every file. dB and multiplier are linked (+6 dB ≈ 2x). The output filename carries the gain as a suffix (e.g. `_vol+6dB`) and you can grab everything as a ZIP.

FAQ

Is audio uploaded?: No. ffmpeg.wasm runs inside your browser; audio never leaves your device.
Adding +6 dB causes distortion — why?: Positive gain pushes peaks above 0 dBFS and clips, unless the source had headroom. Cutting (-3 to -6 dB) is the safe direction. Boosting cleanly requires a limiter / mastering chain, which this tool does not include.
How are dB and multiplier related?: multiplier = 10^(dB/20). +6 dB ≈ 2x, +12 dB ≈ 4x, -6 dB ≈ 0.5x, -20 dB ≈ 0.1x. Useful rule of thumb: 'double the level' is roughly +6 dB.
Same output format as input?: Same extension. The volume filter requires re-encoding, so the codec is re-encoded with ffmpeg defaults (mp3 → libmp3lame, wav → pcm_s16le, aac → aac, ogg → libvorbis, etc.). Bitrate is left to ffmpeg's defaults.
Same gain for every file?: Yes — the single slider value is applied to all dropped files. If you need per-file gains, run the tool once per file.

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