Booster Volume

Online Audio Normalizer

Normalizing means adjusting a recording so its level sits at a consistent target. This tool does it two ways: it can analyse the file and apply exactly the gain needed to bring its loudest peak to just under full scale, and it can compress the file so that quiet passages rise relative to loud ones.

Normalize a file

Audio normalizerPeak analysis with automatic gain matching, plus adjustable compression for level consistency.

Drop an audio or video file here, or choose one. It is processed on your device and never uploaded.

Processed on your device — nothing is uploaded. Loud audio can damage hearing: lower your system volume before boosting, then raise it gradually.

Two kinds of normalization

They solve different problems and are often confused.

  1. Peak normalization

    The tool scans the whole file, finds the single loudest sample, and calculates the gain that would bring it to just below the ceiling. Press Analyse and normalize to apply it. This is lossless in the sense that nothing is reshaped — every sample is multiplied by the same number. It is also limited: one loud cough can hold the entire file back.

  2. Loudness normalization by compression

    Raise the compression control and the tool reduces the difference between loud and quiet parts, then applies makeup gain. The average level rises even though the peak does not. This is what actually makes a wildly inconsistent lecture recording listenable, and it is what streaming platforms do to your uploads.

When peak normalization disappoints

A common frustration: you normalize a quiet recording, the tool reports it applied barely any gain, and it still sounds quiet. This almost always means the file already has a peak near full scale — a door slam, a chair scrape, a plosive on a microphone — even though the average level is low.

Peak normalization can only work with the headroom above the highest peak, and there is none. Compression is the answer here, because it lowers that isolated peak so the rest of the file can come up. There is more on the distinction in what is audio normalization.

Frequently asked questions

Does normalizing damage audio quality?

Peak normalization does not — it is a single multiplication applied uniformly. Compression-based normalization does change the audio, by design: it reduces dynamic range. Whether that is damage depends on the material. For a lecture recording it is an improvement; for orchestral music it removes something musically meaningful.

Is this the same as LUFS normalization?

Not exactly. Broadcast and streaming standards measure integrated loudness in LUFS, which is a perceptual measure weighted by frequency. This tool works from peak analysis and a compressor, which is simpler and runs in real time in the browser but is not a calibrated LUFS meter.

Why does the analysis take a moment?

It decodes the entire file and scans every sample to find the true peak. On a long file that is a lot of data, so it runs once and caches the result.

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