You do not need a server to build a useful audio trimmer. Modern browsers can decode an audio file, let the user select a time range, and generate a downloadable clip without uploading the source file anywhere. This tutorial walks through the core of a small ringtone editor using the Web Audio ...
Source: [Dev.to](https://dev.to/athena886/how-to-build-a-browser-based-ringtone-editor-with-the-web-audio-api-3hp4)