Before you start
- Your Apple Account (for iCloud) or a Google account (for Google Photos)
- Wi-Fi, if you upload photos to the cloud
Method 1 Find out what’s taking up space
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Step 1: Open iPhone Storage
Go to Settings > General > iPhone Storage. Wait a moment for the coloured bar and app list to load.
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Step 2: Read the recommendations
iOS suggests quick wins at the top, such as reviewing large attachments or offloading apps. Each one shows how much space you’d save.
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Step 3: Look at the biggest apps
Apps are sorted by size. Tap any app to see how much is the app itself and how much is its Documents & Data.
Method 2 Keep photos in the cloud, not on your phone
Prefer Google? Install Google Photos, turn on Backup, and once everything is backed up use Free up space in the app. Only do this after checking your photos appear at photos.google.com.
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Step 1: Turn on iCloud Photos
Go to Settings > Photos (or Settings > [your name] > iCloud > Photos) and turn on Sync this iPhone / iCloud Photos.
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Step 2: Choose Optimize iPhone Storage
Select Optimize iPhone Storage. Full-resolution photos and videos are kept in iCloud, and smaller versions on your phone. Originals download when you open them.
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Step 3: Make sure you have enough iCloud space
The free plan is 5 GB. If your library is larger, an iCloud+ plan (from 50 GB) is the simplest option.
Method 3 Offload apps you rarely use
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Step 1: Turn on automatic offloading
Go to Settings > Apps > App Store (on older iOS: Settings > App Store) and turn on Offload Unused Apps.
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Step 2: Or offload one app
In Settings > General > iPhone Storage, tap a large app and choose Offload App. The app is removed but its data stays.
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Step 3: Reinstall when needed
The app icon stays on your Home Screen with a small cloud. Tap it to reinstall with everything as you left it.
Method 4 Clear the hidden space hogs
What is “System Data” and can I reduce it?
System Data (formerly “Other”) includes caches, logs and temporary files. It grows and shrinks on its own. Restarting your iPhone and clearing Safari data often reduces it. If it stays above 15–20 GB for weeks, backing up and restoring the iPhone is the only reliable reset.
Troubleshooting
Storage is still full after Optimize iPhone Storage
Optimization happens gradually and only when space is needed. Keep the phone on Wi-Fi and charging overnight. Also check that iCloud isn’t full: Settings > [your name] > iCloud.
iPhone Storage is stuck on “Calculating”
Close Settings, restart the iPhone and open it again. It can take a minute on phones with large libraries.
Photos look blurry after optimizing
That’s the smaller version. Open the photo and wait a second for the full version to download, or make sure you’re online.
Frequently asked questions
Does offloading an app delete my data?
No. Offloading removes only the app. Your documents, settings and logins stay, and come back when you reinstall it.
Will Optimize iPhone Storage lower my photo quality?
No. The full-quality originals are safely stored in iCloud and download whenever you open, share or edit a photo.
How much free space should I keep on my iPhone?
Aim for at least 10% free, or about 5–10 GB. Less than that can slow your phone and stop updates from installing.
Can I move photos to a computer instead?
Yes. Connect to a Mac (Photos app) or Windows PC (Photos app or File Explorer), import them, check the copies, and only then delete them from the phone.
Summary
The biggest wins are iCloud Photos with Optimize iPhone Storage, Offload Unused Apps, and clearing large Messages attachments and downloaded media. Your photos stay safe in the cloud while your iPhone gets its space back.
