Audio Volume Booster

Gain, peak normalization and loudness normalization: what's the difference?

These three modes solve different problems, and this audio volume booster gives you all three instead of picking one for you. Gain is the simplest: it multiplies the whole signal by a fixed amount, raising or lowering everything equally. It is direct, but it takes your own judgment to know how much is too much, since gain alone does not check where the loudest peaks end up.

Peak normalize instead looks at the single loudest sample in the file and scales the whole thing so that peak lands exactly on a target ceiling. It is predictable and fast, but it only cares about the highest point — two files with the same peak level can still sound very differently loud to a listener, depending on how much of each track sits near that peak.

Loudness normalize targets integrated LUFS instead — a measurement of average perceived loudness across the whole file, not just its highest point. This is what correlates most closely with how loud something actually sounds to a person, and it is the method streaming services and broadcasters use to keep listening levels consistent from one piece of audio to the next.

True peak and why dBTP matters

Sample peak is the highest value in the digital audio data itself. True peak, measured in dBTP, estimates the highest point the analog waveform actually reaches after it is reconstructed for playback — and that reconstructed peak can be higher than the sample peak suggests, especially right around 0 dBFS. That gap is why a file that looks fine in sample-peak terms can still clip on some playback systems or after conversion to a lossy format.

The limiter in this tool uses 4x oversampled detection specifically to catch those in-between peaks, not just the ones that land exactly on a sample. Setting your ceiling a little below 0 dBTP, rather than right at it, leaves margin for that reconstruction and for any further lossy encoding downstream, which is why the default ceiling options all sit below zero rather than at it.

Loudness range: how much the level varies

Loudness range, measured in LU, describes how much a file's loudness varies over its length — a tightly compressed pop master has a small loudness range, while a dynamic classical recording or a conversation with quiet and loud moments has a much larger one. The analysis panel reports loudness range alongside integrated LUFS so you can see not just how loud a file is on average, but how much it moves around that average.

A very small loudness range after normalization can be a sign that a track was already heavily compressed before it reached you, while a very large one on a podcast episode often means some sections need manual gain riding rather than a single blanket target. Neither number alone tells the whole story, but reading them together gives a fuller picture than integrated LUFS on its own.

Loudness targets: streaming, podcasts and broadcast

Different platforms and formats expect different integrated loudness levels, which is why Loudness normalize gives you several ready-made targets instead of a single default value to fight against every time. Matching the target a platform actually expects avoids the file being turned down automatically on playback, or standing out as noticeably quieter or louder than everything around it in a playlist.

Pick the target that matches where the file is actually headed rather than guessing at a single number for everything you export. A podcast destined for a stereo feed and one destined for a mono phone-call-style feed genuinely need different targets, which is why podcast mode splits into separate stereo and mono options below rather than offering just one shared number.

Why louder isn't always better, and how the limiter prevents clipping

Pushing a file louder without limiting risks clipping — peaks that exceed 0 dBFS get flattened off, which sounds harsh, crackly and distinctly worse than the original, no matter how loud it now is. "Louder" and "better" are not the same thing, and a heavily clipped file that measures loud can still sound like a clear downgrade to a listener.

That is what the true-peak limiter is for: it catches peaks before they cross your chosen ceiling, so even an aggressive boost or a demanding loudness target does not produce hard clipping on export. If a target genuinely requires pushing the file hard, this tool warns you that heavy limiting is being applied — worth noticing, since very heavy limiting can itself introduce audible pumping even without outright clipping.

What to expect

Normalizing a quiet, noisy phone recording up to a louder target raises the noise floor along with the signal, so background hiss or hum that was easy to ignore at a low level can become noticeable at a higher one — running noise remover first often helps. Loudness normalization changes average level, not the underlying dynamic character of a recording, and it cannot repair clipping or distortion that was already present in the source file before you opened it here.

For shaping tone rather than level, use the equalizer — cleaning up mud or harshness before boosting tends to give a cleaner result than boosting first and fixing problems after. And if all you need is more low end rather than more overall level, bass boost is the more direct tool, since it targets one frequency range instead of the whole signal at once.

Guides for this tool