This is a simple implementation of audio level normalization in Javascript. Such normalization is useful if you are listening to recordings with hugely different loudness levels and want to have them all keep the same level.
It bases partially on the ReplayGain algorithm, but doesn't implement it fully.
Useful links:
You can open the normalizer.html file in the browser and see the algorithm in action.
You'll need a local http server most likely as most browsers forbid fetch on the file:// protocol.
This is licensed under the terms of the MIT license and the Apache License (Version 2.0), at your option.
The audio files were obtained from the Mozilla Common Voice project and stand under CC-0.