SongSweepYou open iPhone Storage to find out why your phone is full, and the Music app sits at the top with a huge Documents & Data number, although you downloaded almost nothing.
I cannot give you an official fix, because Apple documents none. Below is what is known, what users report, and what each step costs you.
What is Documents & Data in the Music app?
In iPhone Storage, every app shows its size split into the app, its documents and data, and for Music also your downloaded songs. Documents & Data is the Music app's own cache and database. It is not your downloaded music.
That is why removing downloads does not shrink it. For the download side of the story, see why Apple Music takes so much storage.
How big can it get, and does Apple say why?
In Apple Community threads, users describe Documents & Data of tens of gigabytes after updating to iOS 26, with no downloaded songs. I could not find an Apple statement about the cause or a documented fix.
So treat everything below as user reports, not as official advice. Check the numbers first, so you know whether this is your problem.
What do users report helps?
Start at the top and stop when the number is back to normal. Each step costs you more than the one before.
- Open Settings > General > iPhone Storage > Music and note the size of Documents & Data
- Try Offload App, if your iPhone offers it for Music
- Delete the Music app and reinstall it from the App Store. Your downloads must be downloaded again
- Turn Sync Library off and on again in Settings > Music. This removes downloaded songs, and your library view can change until it syncs back
- Check the size again
What does each fix cost you?
Your music itself stays in your Apple Music account, because it lives there and not only on the phone.
| Step | What you lose | Risk |
|---|---|---|
| Offload App | Nothing you chose | Low, may not be offered for Music |
| Delete and reinstall Music | Your downloads | Medium, you download again |
| Sync Library off and on | Downloaded songs, and the library view until it syncs back | Higher, do it on Wi-Fi and with time to spare |
Does cleaning up my library shrink Documents & Data?
I cannot promise that. A smaller library is a good idea for other reasons, but I have no evidence that it changes this number. SongSweep does not change storage: it moves sorted-out songs to a playlist and sets Suggest Less, and deleting songs happens in the Music app.
When should you contact Apple?
If Documents & Data stays huge after these steps, report it to Apple Support and add your iOS version. More reports are the only way a fix becomes official.