Free up app storage

Free up Mastodon storage

The official Mastodon app caches timeline photos and videos so the home feed scrolls. Posts you already published stay on your server. Official Mastodon docs cover install, compose, and preferences. They do not document a Free up Storage screen.

See how much space Mastodon is using

iPhone

1. Open the iPhone Settings app.
2. Tap General > iPhone Storage.
3. Tap Mastodon.

Android

1. Open your phone Settings > Apps (or Apps and notifications).
2. Tap Mastodon.
3. Tap Storage or Storage and cache.

Media cache is this phone. Your posts live on the instance you joined.

Media cache

Avatars, attached images, and boosted video sit in cache. Android Clear cache drops them. Server posts stay. The next scroll downloads media again.

1. Open Mastodon and tap Profile, then the gear if you want filters or posting defaults.
2. Look for Clear cache or Storage. Official docs do not list one.

If that row is missing, use Android Clear cache below. Do not invent a cleaner that is not there.

Composer drafts

Text you started with the pencil button can sit on this phone until you post or discard it. Open compose and delete leftover drafts. Attached photos in an unsent post are local. Published posts stay on the server.

Saved images on the phone

If you saved a post image to Photos or Gallery, that copy is outside Mastodon. Delete it there, including Recently Deleted / Trash.

Clear Mastodon cache on Android

1. Open your phone Settings > Apps > Mastodon.
2. Tap Storage or Storage and cache.
3. Tap Clear cache.

Do not tap Clear storage / Clear data unless you mean to reset Mastodon. That signs you out of the instance and can drop local drafts. Server posts stay.

iPhone does not offer a separate Mastodon cache button. Offload the app in iPhone Storage if the system total stays high.

Reinstall the app if storage is still high

If you already cleaned media and Mastodon still looks huge, a fresh install can clear leftover cache and temp files that are hard to reach by hand.

1. Posts stay on your Mastodon server. Save any local drafts and attached media you still want. You will sign in to the same instance after reinstall.
2. Delete the app from your phone.
3. Restart your phone.
4. Install Mastodon again from the App Store or Google Play.
5. Sign in and restore from backup if the app offers it.

This often frees a lot of space. You may need to download some media again after restore.

What to do next

After Mastodon is lighter, check your photo library for duplicates and similar shots. That is what Dedupo is for.

More app guides: Free up app storage.