Volume Booster (Increase Audio Volume)

Make a quiet recording, voice memo, podcast or song louder. Turn it up by a set number of decibels, or let the tool maximise it so the loudest moment sits just under full scale. A look-ahead limiter catches the few peaks that would otherwise clip and distort, and the results show peak and average (RMS) levels before and after. Everything runs in your browser; files are never uploaded.

How to use this tool

1. Choose one or more audio files.
2. Pick "Turn up by a set amount" and a gain (+6 dB is a good start), or "Maximise".
3. Keep "Prevent clipping" on unless you want the raw gain.
4. Choose the format and press Calculate; compare the before and after levels.

Formula

Gain factor = 10^(dB ÷ 20) · Maximise gain (dB) = −1 − peak (dBFS) · level (dBFS) = 20 × log10(amplitude)

+6 dB doubles every sample value. The limiter looks 5 ms ahead and lowers the gain smoothly before a peak would pass −1 dBFS, then recovers over about 80 ms, so only the loudest moments are touched. Maximise applies one fixed gain to the whole file and never needs the limiter. For MP3, M4A, OGG and Opus the encoded file is decoded again and, if the encoder pushed any peak over full scale, lowered and encoded once more.

Example

A recording peaking at −8.7 dBFS with an average of −11.7 dBFS, boosted by +6 dB, peaks at −2.7 dBFS and averages −5.7 dBFS: every sample is 10^(6 ÷ 20) ≈ 2 times larger. Maximising it instead adds 7.7 dB, bringing the peak to −1 dBFS.