What cache is and why your iPhone stores it
Cache is temporary data that apps and your web browser save on your phone to load faster next time. When you open Instagram, it stores thumbnail images. When you visit a website, it saves parts of the page layout. Your iPhone does this automatically — you never ask it to.
Cache speeds things up because retrieving data from your phone's storage is much faster than downloading it again from the internet. The trade-off is that cache takes up storage space, and sometimes outdated cached data causes an app to behave strangely — showing old information, freezing, or crashing.
Your iPhone stores cache in different places depending on what created it. Safari (the built-in browser) keeps its own cache. Each app keeps its own cache inside its folder. Your phone's system itself caches data too. Clearing one does not clear the others.
Key Takeaways
- Cache is temporary data apps save to load faster, and clearing it frees up storage and can fix apps that are frozen or showing old information.
- Safari cache, app cache, and system cache are stored separately, so you may need to clear more than one depending on what is not working.
- Clearing cache does not delete your passwords, login information, or any files you created — it only removes temporary data.
- You can clear Safari cache through Settings, clear individual app cache through Settings, or clear all app cache at once by offloading apps.
How to clear Safari cache on your iPhone
Open Settings, then scroll down and tap Safari. Scroll to the bottom of the Safari settings page and tap Clear History and Website Data. A menu will appear asking what time period to clear — tap All time to remove everything, or choose a shorter window like Last Hour or Today if you only want to clear recent browsing.
After you tap your choice, Safari will clear the cached website data, browsing history, and cookies all at once. This is the fastest way to free up space if Safari is running slowly or if a website is showing you outdated information.
If you want to keep your browsing history but only clear cached data, there is no separate toggle for that in Settings. Your only option is to clear history and data together, or to use Safari's private browsing mode going forward (which does not save cache at all).
How to clear cache for individual apps
Most apps store cache inside their own folder, and you can clear it without deleting the app itself. Open Settings, then tap General, then iPhone Storage. You will see a list of all your apps ranked by how much space they use.
Find the app that is misbehaving or taking up too much space, and tap it. You will see two options: Offload App and Delete App. Tap Offload App. This removes the app but keeps your login information and any data you created inside it (like photos in a photo app, or notes in a notes app). When you reinstall the app later, your data will still be there.
Offloading clears the app's cache because it removes the app's temporary files. If you want to reinstall the app right away, tap Reinstall App on the same screen, and it will read fresh from the App Store without the old cache.
If you want to clear cache without offloading, some apps have their own cache-clearing option buried in their settings. Open the app, go to its settings or preferences (usually a gear icon or menu), and look for options like Clear Cache, Storage, or Data. Not every app offers this, so offloading is often the more reliable method.
How to clear system cache without deleting apps
Your iPhone's operating system itself caches data — temporary files from updates, system processes, and background tasks. You cannot clear this cache through a single Settings menu the way you can with Safari.
The most direct method is to restart your iPhone, which clears some system cache automatically. Hold down the power button and volume button together until you see the power-off slider, then slide to power off. Wait 10 seconds, then hold the power button again until you see the Apple logo.
If you want to clear more system cache, you can back up your phone to iCloud, then go to Settings > General > Transfer or Reset > Reset > Erase All Content and Settings. This removes everything and clears all cache, but you will need to restore from your backup afterward. This is a more drastic step and is usually only necessary if your phone is extremely slow or you are selling it.
What clearing cache does and does not do
Clearing cache removes temporary data only. It does not delete your passwords, login information, or anything you actively created. If you clear Safari cache, you will be logged out of websites, but your saved passwords remain in your keychain. If you offload an app, your account information and files stay on Apple's servers or the app's servers.
Clearing cache also does not remove viruses or malware — cache is just temporary data, not executable code. If your phone is behaving strangely because of malware, clearing cache will not fix it. If your phone is slow because storage is full, clearing cache helps only if cache is actually taking up significant space, which you can check in iPhone Storage.
The main reasons to clear cache are: freeing up storage space, fixing an app that is frozen or showing outdated information, or speeding up your phone if it is running slowly. If none of those explore, there is no urgent reason to clear cache regularly.
When you should and should not clear cache
Clear cache if an app keeps crashing, if a website is showing you information from weeks ago, or if your iPhone storage is nearly full and you need space. You can check how much space cache is using by going to Settings > General > iPhone Storage and looking at individual app sizes — if an app shows 500 MB or more and you have not used it recently, offloading it will free up that space.
Do not clear cache if you are about to lose internet connection and want to keep websites available offline, or if you rely on cached login information to access apps quickly. Do not clear cache thinking it will speed up your phone if your storage is not actually full — cache is only a problem if it is taking up meaningful space or causing specific apps to malfunction.
There is no benefit to clearing cache on a schedule. Clear it when you have a specific reason: something is broken, you need storage, or you are troubleshooting a problem. Otherwise, your iPhone manages cache on its own and will delete old cache automatically when it needs space.
Frequently Asked Questions
Will clearing cache log me out of everything?
Clearing Safari cache will log you out of websites because cookies (which store login sessions) are deleted along with cache. Offloading an app will not log you out because your account credentials are stored separately from cache. When you reinstall the app, you will still be logged in.
How much space does cache usually take up?
It varies widely. Safari cache might be 50 MB to 500 MB depending on how many websites you visit. Individual apps can cache anywhere from 10 MB to several gigabytes. You can see exactly how much each app is using by going to Settings > General > iPhone Storage and tapping the app name.
Can I clear cache automatically on a schedule?
iOS does not have a built-in automatic cache-clearing schedule. You can clear Safari cache manually whenever you want, or you can enable Settings > Safari > Clear History and Website Data to happen automatically when you close Safari, though this option is not available in all iOS versions.
Is it safe to clear cache?
Yes. Clearing cache removes only temporary data and does not affect your files, photos, messages, or account information. The worst that can happen is an app takes slightly longer to load the first time after you clear its cache.
What is the difference between clearing cache and clearing cookies?
Cache is temporary data like images and page layouts. Cookies are small files that store login sessions and website preferences. When you tap Clear History and Website Data in Safari, you clear both at once. Some apps let you clear one without the other, but most do not offer that choice.