Quick answer
To clean up iPhone storage, open Settings › General › iPhone Storage to see what is using space. Then work through the biggest items: offload apps you rarely use, turn on iCloud Photos with Optimize iPhone Storage, delete old videos and empty Recently Deleted, and set Messages to keep conversations for a year instead of forever.
How to check what is using your iPhone storage
Start in iPhone Storage, because the right fix depends on what is actually filling your phone. Someone with a huge photo library needs a different plan from someone with a few bloated apps.
- Open
Settings › General › iPhone Storage. - Wait a moment while the categories are calculated.
- Read the coloured bar at the top. It splits usage into Apps, Photos, Messages, iOS, System Data and more.
- Scroll the app list below it, sorted from largest to smallest.
- Tap any app to see its size split into the app itself and its Documents & Data.
The app list often holds surprises: an app you barely open taking up several gigabytes, or a messaging app holding years of media. Spend a minute here before you delete anything.
Use Apple's built-in recommendations
Near the top of the iPhone Storage screen, iOS often shows recommendations based on how you use the phone. You may see options such as Offload Unused Apps, Review Large Attachments, Auto Delete Old Conversations or Enable iCloud Photos. Each one takes a tap or two and usually targets something real.
- Offload Unused Apps removes apps you haven't used for a while but keeps their data. If you reinstall one, everything is still there.
- Review Large Attachments lists the biggest files shared in Messages, sorted by size. Deleting a few large videos frees more than clearing dozens of small images.
How to free up space taken by photos and videos
For most people, photos and videos use the most storage. Video is the main culprit. A single minute of 4K video at 60 fps can take over 400 MB. You have two ways to deal with it: move the library to iCloud, or trim it by hand.
Turn on iCloud Photos with Optimize iPhone Storage
With iCloud Photos and Optimize iPhone Storage turned on, your full-resolution originals live in iCloud. The iPhone keeps smaller versions and downloads the original when you open a photo.
- Open Settings and tap your name at the top.
- Tap
iCloud › Photos. - Turn on Sync this iPhone.
- Choose Optimize iPhone Storage, not Download and Keep Originals.
iCloud's free tier is 5 GB, which is small next to most photo libraries, so you will likely need a paid iCloud plan. The first upload can take hours or days depending on the size of your library and your connection. Leave the phone on Wi-Fi and power overnight. If uploads stall, our guide to fixing iCloud Photos not syncing covers the usual causes.
Clean up the photo library by hand
If you don't want to pay for iCloud, or simply want a smaller library, the Photos app helps you find what to delete. Open Photos and scroll to the Utilities section.
- Duplicates finds near-identical photos. Merging keeps the best-quality copy and removes the rest.
- Screenshots collects every screenshot you have taken. Most were useful for a day, such as an address or a product, and can go.
- Videos, under Media Types, shows every video. Clips forwarded from chats and long recordings you never watch again are the quickest wins.
Deleted items move to Recently Deleted and stay there for 30 days. They keep using storage until they leave that album, so open it, check that nothing important is there and delete everything to reclaim the space right away. The Clean Up tool can also tidy photos you want to keep, as our Clean Up photos tutorial explains, though it won't save space.
How to reduce app storage
Apps grow well beyond their download size as they cache content and store offline files. The Documents & Data figure in iPhone Storage shows how much each app has piled up.
- Social media apps cache large amounts of content so feeds load faster. Deleting and reinstalling one clears that cache. Your account lives on the service's servers, so signing back in restores it.
- Music, podcast and audiobook apps may download episodes and albums automatically. Remove downloads you no longer need, or stream instead if you are usually on Wi-Fi.
- Games are often the largest apps. Offload ones you are not playing to keep your saves.
| Option | What it removes | What it keeps | Use it for |
|---|---|---|---|
| Offload App | The app itself | Its documents and data | Apps you will want back later, such as games with save files |
| Delete App | The app and all its data on the phone | Only what the app stores on its own servers | Apps you are done with |
How to stop Messages using so much space
Messages keeps every photo, video, GIF and attachment from every conversation unless you remove them. After a few years that adds up, especially in busy group chats.
- Open
Settings › Messages. - Scroll to Message History.
- Tap Keep Messages.
- Change Forever to 1 Year or 30 Days.
That setting deletes older conversations, so check you are happy to lose them first. For a gentler clean-up, tap Messages in iPhone Storage. You can review top conversations, photos, videos, GIFs and other attachments there and delete the largest files one by one.
How to clear Safari data and downloads
Safari keeps cached website data so pages you revisit load faster, and that cache grows over time. To clear it, open Settings › Safari and tap Clear History and Website Data. That also removes your browsing history and cookies, so you will be signed out of websites.
Files you download in Safari stay until you remove them. Check Settings › Safari › Downloads to see where they are saved, then open the Files app and delete old downloads.
How to deal with System Data
System Data holds caches, logs, temporary files and other files iOS manages itself. It can grow to many gigabytes, and there is no button to delete it. You can still shrink it:
- Restart the iPhone. This clears some temporary files. If the phone is frozen, use a force restart.
- Deal with pending updates. A downloaded update waiting to install counts toward System Data. Install it, or tap it in iPhone Storage and choose Delete Update.
- Sign out of streaming apps. Some streaming apps store cached content in System Data. Signing out and back in can release it.
- As a last resort, back up and restore. Erasing the iPhone and restoring a backup is the only way to clear System Data completely.
If you are on a Mac with the same problem, see our guide to cleaning up System Data on a Mac.
Making room for an iOS update or beta
A major iOS update or beta needs much more room than a small point update, because the iPhone downloads and unpacks a complete system. If Software Update says there isn't enough space, the steps above are the quickest way to clear it. Back up before installing either one. A backup made on a beta cannot be restored onto an older iOS version, so our guide to backing up before the iOS 27 beta is worth reading first. For beta-specific numbers, see how much storage the iOS 27 beta needs.
How to keep your iPhone storage under control
Storage rarely fills overnight. It creeps up as caches grow and old apps sit unused, so a few habits stop it coming back:
- Leave Offload Unused Apps turned on so iOS trims apps you stop using.
- Open iPhone Storage once a month to catch anything growing fast.
- Think twice before downloading whole podcast series or offline maps you may not use.
- Clear screenshots and duplicates every few months rather than once every few years.
What to do next
Open iPhone Storage now and deal with the top two or three items on the list. That is usually where most of the reclaimable space sits. If you are clearing room for an update, make your backup next, then install.
Frequently asked questions
How do I see what is taking up storage on my iPhone?
Open Settings › General › iPhone Storage and wait a few seconds while it calculates. The bar at the top splits your storage into categories such as Apps, Photos, Messages, iOS and System Data. Below it, every app is listed by size. Tap any app to see how much is the app itself and how much is its documents and data. That second number is often the surprise.
What is the difference between offloading and deleting an app?
Offload App removes the app but keeps its documents and data on your iPhone. When you reinstall it, you pick up where you left off, which suits games with save files. Delete App removes the app and everything it stored on the phone. Data the app keeps on its own servers, such as your account, is usually restored when you sign in again.
Why does deleting photos not free up space straight away?
Deleted photos and videos go to the Recently Deleted album and stay there for 30 days in case you change your mind. Until they leave that album, they still use storage. To reclaim the space now, open Photos, go to Recently Deleted in the Utilities section, check nothing important is there, and delete everything in it.
How do I clear System Data on iPhone?
There is no button to delete System Data, because it holds caches, logs and temporary files that iOS manages itself. Restarting the iPhone clears some temporary files. Deleting a downloaded but uninstalled iOS update helps too. So does signing out of streaming apps that keep large caches. In extreme cases, backing up, erasing and restoring the iPhone is the only full reset.
Does iCloud Photos free up storage on my iPhone?
Yes, if you choose Optimize iPhone Storage. Your full-resolution photos and videos are kept in iCloud, and the iPhone stores smaller versions that it swaps for the originals when you open them. You need enough iCloud storage for your library, and iCloud's free tier is 5 GB, so most people need a paid plan. The first upload can take hours or days.
How much free space do I need to install an iOS update or beta?
Software Update tells you if there isn't enough room and won't start the install until you clear more. Major updates and betas need far more than a small point update, because the iPhone downloads and unpacks the whole system. Our guide to iOS 27 beta storage space covers the iOS 27 beta specifically.