Audio Loudness Estimate

Compare the approximate loudness, sample peak, and dynamic range of supported audio files. The tool suggests a playback gain; it does not change your files. Processing runs in your browser.

Key features

What is LUFS?

LUFS is a standard unit for perceived loudness. This tool uses a simpler RMS-based estimate rather than a standards-compliant LUFS measurement, so treat the number as a comparison aid.

What is ReplayGain?

ReplayGain metadata lets compatible players adjust playback volume. This tool suggests a gain relative to its estimated -14 LUFS target; a positive value means it would turn the track up.

Note on accuracy

This tool omits the K-weighting and true-peak oversampling used by standards-compliant meters. Its estimates may differ substantially from a certified loudness measurement.

Common use cases

Find loud or quiet tracks in your library

Scan individual tracks to identify outliers — songs that are dramatically louder or quieter than the rest of your playlist.

Get a ReplayGain adjustment value

Use the suggested gain to write a ReplayGain tag in your audio files, enabling volume normalization in OFPlayer, foobar2000, and other ReplayGain-aware players.

Check sample peaks

Look for tracks with high sample peaks. This check does not measure inter-sample peaks or prove that clipping occurred.

Frequently asked questions

What loudness target should I use?

There is no single target for every library. The default -14 LUFS estimate is a comparison point; choose a level that works for your player and collection.

Is K-weighting applied?

No. This tool uses an RMS-based estimate without K-weighting. Its output is not a standards-compliant EBU R128 measurement.

Is my audio uploaded?

No. All processing runs locally in your browser using the Web Audio API.