In this guide
Changing project tempo slows regions that follow it; it does not automatically stretch every imported recording. On an eligible audio region, check Follow Tempo & Pitch before lowering the project tempo. Compare the result with the original and verify timing and pitch.
To slow down audio in GarageBand, first check whether the region follows the project tempo. For an eligible audio region, enable Follow Tempo & Pitch in its region settings, then lower the project tempo and listen to the result. Changing the tempo alone does not reliably stretch every imported recording. Keep the original file and a copy of your project so you can compare and undo changes.
GarageBand for Mac and GarageBand for iPhone have different controls. A tempo change can affect other regions in the project too. If you only need a slower standalone file, a separate pitch-preserving speed changer may be simpler than changing an entire arrangement.
Before changing the tempo
For a steady song, note the source's approximate beats per minute and the project tempo. Set up a working copy with the project tempo matching the recording before changing the target, and listen for unexpected stretching when you enable tempo following. An incorrect source tempo, variable-tempo performance, or imported file without reliable tempo information can make the grid and the audio disagree.
For example, if a correctly aligned 120 BPM region follows the project tempo, changing the project to 90 BPM targets 75% of the original tempo (90 ÷ 120 = 0.75). The audio should take longer, not shorter. Treat that as a target, then verify the actual result; time-stretch processing can affect transients and texture. If you need to estimate a steady pulse first, try the song BPM finder or tap tempo and check the result by ear.
Slow an eligible audio region in GarageBand on Mac
- Save a working project. Open a copy, check its current tempo, and import or select the audio region you want to change. Listen to the original before enabling tempo following.
- Open the region controls. Select the audio region in the Tracks area and open the Audio Editor. In the region controls, look for Follow Tempo & Pitch and enable it when available. Apple notes in its GarageBand for macOS release notes that enabling this setting can also enable Flex in the Track Editor.
- Lower the project tempo. Adjust the tempo in the control bar to a lower value, for example 90 BPM from 120 BPM when the original is correctly aligned to 120 BPM. Project tempo affects the arrangement, so check other regions and the metronome too.
- Listen and compare. Check that the region actually became slower and that its start, end, pitch and timing against the other tracks remain appropriate. If it changed unexpectedly when Follow was enabled, undo and revisit the source and project tempo instead of assuming the new BPM is correct.
- Export a copy. Use GarageBand's sharing/export controls for the desired audio file, then open the saved file separately and listen to its beginning, a busy passage and its ending. Keep the editable project and original recording.
The Follow control depends on the selected region and version; do not assume an unavailable checkbox means the project tempo will stretch that file. A project-wide change may also affect loops and instrument parts. For independent processing of one file, use a separate time-stretch workflow and reimport the result.
Slow a project or audio region on iPhone
In GarageBand for iPhone, open Settings → Tempo and lower the tempo for the song. Apple says Touch Instrument recordings generally follow the new tempo, except Audio Recorder and Amp recordings; Apple Loops also follow. See Apple's song-settings guide.
For a blue audio region, double-tap the region, choose Settings and look for Follow Tempo & Pitch. Apple describes that option for blue regions in its region-settings guide. Enable it when available, change the song tempo, and listen to confirm the actual result. The setting also relates to key, so check pitch as well as speed.
Apple's import instructions warn that imported audio files, apart from Apple Loops, do not follow tempo changes by default. Set the song section to Automatic if you need the complete file, and verify that the region and settings in your installed version support the edit. Do not assume a lower project number means your imported recording changed speed.
Why didn't the recording slow down?
| What happened | What to check |
|---|---|
| The click slowed, but the recording did not | Check the selected audio region and whether Follow Tempo & Pitch is available and enabled. Imported audio may not follow automatically. |
| The clip changed immediately or no longer lines up | Undo and compare the source tempo with the project tempo. Check the region's start and tempo information before trying again. |
| The voice sounds stretched or watery | Try a smaller change, compare a different processing method, or use a shorter practice excerpt. Time stretching can create artifacts. |
| The track ends early | On iPhone, check song-section length and whether the full recording was imported. On either device, check the export range. |
| Other instruments changed too | The project tempo can affect multiple regions. Work in a project copy or process a single file separately. |
Make a slower file without changing the GarageBand project
The free Saturalabs audio speed changer processes supported short MP3 or WAV files locally and prepares a pitch-preserving WAV or MP3 at a selected speed from 0.5× to 2×. Choose 0.75× to target a 25% slower playback rate, prepare the file, and listen to the actual output before downloading. The tool does not edit a GarageBand project; import the saved file separately if you need it on a track.
For limits, a BPM calculation and ways to check stretching artifacts, see how to slow down a song without changing pitch. Keep the original: exporting MP3 creates a new lossy file and can add delay or padding.
Common questions
Does changing GarageBand's tempo change the pitch?
Tempo-following and pitch-following settings can depend on region and project key. Keep the key unchanged when you only want a tempo change, then listen and compare notes with the original; stretching is not guaranteed to be artifact-free.
Can I slow only part of a song?
For a short practice passage, prepare an excerpt separately and slow that file. In a multitrack project, changing project tempo may affect other regions, so make a copy and check the timing of the whole arrangement.
Why is the slower audio longer?
A slower playback rate takes more time to play the same material. At 0.75×, a 60-second passage ideally takes about 80 seconds, before any processing or export differences.