Audio Speed Changer

Changing the tempo of a recording sounds trivial, but it is not - at least not if the voice should stay normal. Play a file back naively faster and the pitch rises with it, and everyone sounds like a wound-up cartoon character. The Audio Speed Changer does it right: it changes the tempo and keeps the pitch constant so the voice stays natural.

You load your audio file via drag and drop or the file dialog and choose a speed. Ready presets from 0.5x through 1.25x and 1.5x to 3x cover the typical needs - slower for note-taking or practising, faster for a quick listen-through. The tool immediately shows the estimated new runtime so you know how long the file will be after the change.

Faster is the classic: podcasts, lectures and audiobooks can be heard at 1.25x or 1.5x without losing content - you simply save time. Slower has its place just as much: voice recordings for transcription, music pieces to play along to, unclear passages you want to understand word by word. From 0.5x to 3x, the full range is there.

The actual processing runs server-side with FFmpeg, the standard for audio and video editing. That ensures a clean result without the artefacts that cheap tempo tricks often leave behind. Files up to 100 MB are allowed, which covers practically every podcast episode, lecture or voice recording.

Once the file is ready, you download it directly or store it in the Aktenschrank, the Werkzeu.ge file manager, with one click. That way you have your tempo-adjusted version right in your archive instead of hunting for it in the downloads folder.

The Audio Speed Changer is part of the audio tool family. If the format does not fit, convert it first with the Audio Converter; if you only need a section, the MP3 Cutter helps; and for several files there is the Audio Merger. Everything runs in the browser, without having to install heavy desktop software.