MixMasterAIVolume Booster
A flat gain stage — add or subtract decibels uniformly across the file. The right tool when audio came in too quiet (phone recording, distant mic, voice memo) and you just need to lift the whole thing up. Not a fix for dynamic range; that's what a compressor or limiter is for.
If peaks already touch 0 dBFS, boosting will clip them. The tool warns you when that happens — use a limiter instead.
How it works
Drop the file
MP3, WAV, FLAC, OGG, M4A, AAC, or AIFF. Audio decodes locally.
Up to 200 MB
Pick a gain value
+3 dB roughly doubles perceived loudness. +6 dB is a noticeable lift. +9 dB and beyond starts risking clipping unless your source is very quiet. Negative values reduce volume — useful when audio is too hot.
ffmpeg filter: volume=Xdb
Process
ffmpeg applies the gain and writes a fresh 16-bit WAV. Compare against the source — if peaks now sit at 0 dBFS, back off the gain or run the result through a limiter instead.
Output: 16-bit WAV at source sample rate
Frequently asked questions
Boost vs normalize — which do I want?
Boost is a fixed dB shift applied to everything. Normalize scales the file so a specific point (peak or LUFS) lands at a target value. Use boost when you know the source is quiet and you just want it louder. Use normalize when you're matching a target loudness (Spotify -14 LUFS, Apple -16 LUFS) or evening out volume across multiple recordings.
Why does my audio clip when I boost?
Digital audio caps at 0 dBFS. If your source peaks at -3 dBFS and you add +6 dB of gain, the new peak would be at +3 dBFS — except it can't go there, so it clips at 0 dBFS and you get distortion. To make audio louder without clipping, use a limiter instead of a flat boost.
Does this work on video files?
No, just audio. To boost audio on a video, extract the audio track first (most video editors do this), boost it here, then re-attach it to the video in your editor.
What about loud parts vs quiet parts?
A flat boost lifts everything by the same amount — quiet parts stay quiet relative to loud parts. To even out dynamics (make quiet parts louder without making loud parts louder), use a compressor or normalizer.