Audio Volume and Loudness
Raise or lower the volume by decibels or percent, or switch on automatic normalization to match a broadcast loudness target. Everything runs in your browser.
The conversion engine (about 32 MB) loads once on your first run and starts instantly from cache afterwards.
Decibels or percent?
Decibels are the standard unit: +6 dB roughly doubles the amplitude and −6 dB roughly halves it. Percent is more intuitive — 200% is twice as loud, 50% is half. Both drive the same filter, so use whichever you think in.
What normalization does
Automatic normalization applies EBU R128 loudness normalization with a −16 LUFS target and a −1.5 dBTP true-peak ceiling. It is the right choice when you need several sources — an interview and a voice-over, say — to feel equally loud, and it is a good prep step for podcasts and YouTube.
Avoiding clipping
Push the level too far and the waveform hits the ceiling and distorts. Start at +3 dB and work up. For a recording that came out too quiet, normalization usually sounds better than a raw boost because it does not push the noise floor as hard.
Frequently asked questions
Does raising the volume hurt quality?
The gain itself loses no information, but background noise rises by the same amount, and too much gain clips the waveform. Export to WAV if you also want to avoid re-encoding loss.
How many decibels should I add?
If you are not sure, use automatic normalization — it works out the required gain from the measured loudness. Adjusting manually, +3 dB at a time is a safe way to creep up on it.
Can I level several files at once?
Yes. Select multiple files and they are processed one after another, each with its own download link. With normalization on, they all land on the same loudness target.