Music Analysis & YouTube

Last updated: October 11, 2026

Overview

Slow Down helps musicians practice along with recordings. For YouTube videos, playback always happens in YouTube's official embedded player. This page explains what we analyze, what we keep, and how rights holders can have analysis removed. It is part of our Terms of Service and Privacy Policy.

How YouTube playback works

  • Every YouTube video plays in YouTube's official IFrame player, with its controls, branding and ads intact.
  • Slowing down and speeding up uses the player's own playback rate control.
  • Loops, markers and notes sit beside the player and never change the video itself.

What we analyze

To help you practice, we can detect a song's tempo (BPM), its beats and bar lines, its key and its chord changes. These are facts about a piece of music, like the information on a chord chart. To find the chords, the analysis briefly works out which notes are sounding, in memory only. We keep nothing but the results above: never melodies, lyrics, or the recording itself.

  • Audio files you upload: analyzed on our servers. You confirm you have the right to upload them.
  • YouTube videos with the Slow Down extension: only when you press "Analyze key, tempo and chords", the extension sends short clips (up to 180 seconds) of the audio already playing in your browser to our server for analysis. Each clip is deleted as soon as analysis finishes. See the extension privacy policy.
  • We do not download audio or video from YouTube.

Pitch and vocal tools

The Slow Down extension can transpose pitch and reduce vocals for the video you are watching. This happens on your own computer, in real time, as the video plays. Nothing is recorded or saved, and the YouTube player is not altered.

What we keep

  • The YouTube video ID you saved, until you delete it.
  • The video's title and thumbnail link from YouTube, refreshed at least every 30 days and removed if the video is no longer available.
  • Detected tempo, beat and bar timings, key and chord changes, until you or we remove them.
  • No YouTube audio or video, ever.

For rights holders: removing analysis

If you own or represent a recording or composition and want any analysis of it removed, email theo@theowecker.com with the YouTube link and what you would like removed. You can ask for all of it or specific parts:

  • Chords
  • Key
  • Tempo
  • Pitch and vocal tools for the video

A removal covers every user who has saved the video, now and in the future. Stored results are deleted, new analysis is blocked, and the video page shows that the removal was made at the rights holder's request. We act on requests promptly. Copyright claims about uploaded content follow the process in our Terms of Service.

YouTube's terms

Slow Down uses YouTube API Services. By using Slow Down you agree to the YouTube Terms of Service. Google's handling of data is described in the Google Privacy Policy. You can revoke Slow Down's access to your Google account at any time from Google security settings.