Free up Honkai Impact 3rd storage

Honkai Impact 3rd keeps story-chapter resources, voice files, and update leftovers on the phone. Captains, crystals, and battlesuits stay on your HoYoverse account. Official help covers Repair and cache from Settings. There is no WhatsApp-style Free up Storage button.

See how much space Honkai Impact 3rd is using

iPhone

Open the iPhone Settings app.
Tap General > iPhone Storage.
Tap Honkai Impact 3rd.

Android

Open your phone Settings > Apps (or Apps and notifications).
Tap Honkai Impact 3rd.
Tap Storage or Storage and cache.

Old chapter resources and leftover update files are usually the extra space.

Delete unused resources

Open Honkai Impact 3rd and tap the Ai-chan Phone on the Bridge.
Open Settings, then Resources (some versions put this on the Phone home).
Delete story chapters, event, or voice resources you do not need on this phone.

HoYoverse also lists Voice Pack Resource Management under Phone Settings > Language > Settings > Voice. Use that if unused voice languages are listed. Do not delete folders outside the game.

Repair vs cache

Launch the game but stay on the Press to Play screen.
Tap the tool icon on the right.
Tap Repair only if assets are broken. Official help says this checks and fixes game assets.

Repair re-downloads files. It does not free space. HoYoverse also says to clear cache from Settings if an update is stuck. That is a fix path, not a storage cleaner.

Clear Honkai Impact 3rd cache on Android

Open your phone Settings > Apps > Honkai Impact 3rd.
Tap Storage or Storage and cache.
Tap Clear cache.

Do not tap Clear storage / Clear data unless you mean to reset Honkai Impact 3rd on this phone. That signs you out. Cloud progress stays on the HoYoverse account. Chapter resources download again when you open them.

iPhone does not offer a separate Honkai Impact 3rd cache button. Use the in-app steps on this page, or 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 Honkai Impact 3rd still looks huge, a fresh install can clear leftover cache and temp files that are hard to reach by hand.

Sign in to HoYoverse first. Battlesuits, crystals, and Captain progress stay on the account. Story resources and voice files download again as you play.
Delete the app from your phone.
Restart your phone.
Install Honkai Impact 3rd again from the App Store or Google Play.
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 Honkai Impact 3rd is lighter, check your photo library for duplicates and similar shots. That is what Dedupo is for.

More app guides: Free up app storage.