What to do when your phone slows down because storage is full

A phone that runs out of storage space slows down because the operating system needs free space to write temporary files, cache data, and run background tasks. When your phone is nearly full, it has to work harder to find space for these operations, which makes apps launch slower, photos take longer to save, and the whole device feel sluggish. The fastest fix is to delete files you do not need — photos, videos, old downloads, and cached app data — which immediately frees up space and lets your phone operate normally again.

The amount of storage you need to free up depends on your phone model and how full it is now. Most phones run noticeably better once you have at least 10 to 15 percent of total storage available. If your phone has 128 GB of storage, that means keeping at least 12 to 19 GB free. You can check how much space you are using right now in your phone's settings, and the steps to do that differ slightly between iPhones and Android phones.

Key Takeaways

  • Check your storage in Settings to see which apps and file types are taking up the most space on your phone.
  • Delete photos and videos you have already backed up to a cloud service like Google Photos or iCloud, since they take up the most space.
  • Clear cached data from apps in Settings without losing your account information or saved preferences.
  • Uninstall apps you no longer use, especially large ones like games, which often take up several gigabytes.
  • Move files to cloud storage or a computer to free up space without permanently deleting them.

Check which files are using the most storage

On iPhone: Open Settings, tap General, then tap iPhone Storage. You will see a list of apps ranked by size, with the largest at the top. Below the apps, you will see a breakdown showing how much space is used by Photos, iCloud Drive, Mail, and other categories. Tap any category to see more detail — for example, tapping Photos shows how many photos and videos you have and how much space they use.

On Android: Open Settings, tap Storage or Storage and USB, then tap Other Apps or Internal Storage. You will see a list of apps ranked by size. Scroll down to see the total amount of free space at the bottom. Some Android phones also show a breakdown by category (Photos, Videos, Downloads, etc.) — if yours does, tap that to see what types of files are taking up the most room.

Once you know what is using space, you can decide what to delete. Photos and videos are almost always the largest files on a phone, followed by apps, then cached data from those apps.

Delete photos and videos you have already backed up

Photos and videos take up far more space than anything else on your phone. Before you delete them, make sure they are saved somewhere else — either in a cloud service like Google Photos, iCloud, OneDrive, or Dropbox, or copied to a computer.

If you use Google Photos on Android: Open Google Photos, tap your profile picture in the top right, then tap Photos Settings. Tap Backup and Sync and make sure it is turned on. Wait for the backup to finish — you will see a checkmark next to each photo once it is saved to Google's servers. Then go back to your phone's storage settings, find Photos, and delete the ones you no longer need. The backed-up versions will still be in Google Photos.

If you use iCloud on iPhone: Open Settings, tap your name at the top, then tap iCloud. Tap Photos and make sure iCloud Photos is turned on. Wait for your photos to upload — this can take hours if you have thousands. Once they are uploaded, open the Photos app, tap the Library tab at the bottom, then tap Select in the top right. Tap the year or month to select multiple photos at once, then tap Delete and confirm. The photos stay in iCloud and you can view them anytime, but they no longer take up space on your phone.

If you do not use a cloud service, connect your phone to a computer with a USB cable and copy your photos to a folder on the computer before deleting them from your phone.

Clear cached data from apps without losing your settings

Apps store temporary files called cache to load faster the next time you open them. Over time, this cache can grow to hundreds of megabytes or even gigabytes. Clearing it frees up space without deleting your account information, messages, or saved preferences.

On iPhone: Open Settings, tap General, then tap iPhone Storage. Tap any app in the list, then tap Offload App. This removes the app but keeps your data. Wait a few seconds, then tap Reinstall App to put it back. The app will be smaller because the cache is gone, but your login information and settings will still be there. Repeat this for the largest apps.

On Android: Open Settings, tap Apps or Application Manager, then tap the app you want to clear. Tap Storage, then tap Clear Cache. This removes temporary files but keeps your account and settings. You can also tap Clear Storage to remove everything, but that will log you out and delete saved data, so only do that if you plan to uninstall the app.

Uninstall apps you no longer use

Apps are the second-largest use of storage after photos. Games in particular can take up 2 to 5 gigabytes each. If you have not opened an app in months, uninstalling it frees up significant space.

On iPhone: Open Settings, tap General, then tap iPhone Storage. Scroll through the list and look for apps you do not use. Tap any app, then tap Delete App, then tap Delete to confirm. The app is removed, but you can reinstall it later from the App Store for free if you change your mind.

On Android: Open Settings, tap Apps or Application Manager, then tap the app you want to remove. Tap Uninstall, then tap OK to confirm. Like iPhone, you can reinstall it later from the Google Play Store.

Do not uninstall system apps that came with your phone — these are usually safe to leave alone, and removing them can cause problems. Stick to apps you downloaded yourself.

Move files to cloud storage instead of deleting them

If you want to keep files but do not have room for them on your phone, move them to a cloud service. This frees up space on your phone while keeping the files accessible from any device.

Google Drive, OneDrive, and Dropbox all work the same way: download the app, sign in, then upload files or folders to your cloud storage. Once they are uploaded, you can delete them from your phone. You can view and edit them anytime by opening the app, and they do not take up space on your phone anymore.

For documents and spreadsheets: Google Drive and OneDrive let you create and edit files directly in the app without downloading them to your phone, which saves even more space.

For photos: Google Photos and iCloud Photos (mentioned earlier) are the easiest option because they back up automatically and let you delete the originals from your phone while keeping them in the cloud.

Restart your phone after freeing up space

Once you have deleted files and cleared cache, restart your phone to let the operating system reorganize its storage and refresh background processes. This often makes a noticeable difference in speed.

On iPhone: Press and hold the side button and either volume button until the power-off slider appears. Drag the slider to turn off your phone, wait 10 seconds, then press and hold the side button again until you see the Apple logo.

On Android: Press and hold the power button until a menu appears, then tap Power Off or Restart. Wait for the phone to turn off, then press the power button again to turn it back on.

Frequently Asked Questions

How much storage should I keep free on my phone?

Most phones run best with at least 10 to 15 percent of total storage available. If your phone has 128 GB, that means keeping 12 to 19 GB free. If you regularly run out of space, consider a phone with more storage or move files to cloud storage more often.

Will clearing cache delete my passwords or login information?

No. Clearing cache removes only temporary files. Your passwords, account logins, and saved preferences stay on your phone. You will still be logged into your apps after clearing cache.

Can I recover photos I deleted from my phone?

If you deleted them from your phone but they are still in Google Photos or iCloud, you can view them there. If you deleted them from both your phone and the cloud service, they are usually gone permanently unless you have a backup on a computer.

Why is my phone still slow after I freed up storage?

Storage is one reason phones slow down, but not the only one. Restart your phone first — this often fixes slowness. If it is still slow, check Settings to see if a background app or process is using a lot of battery or processor power. Older phones also naturally slow down over time as the operating system gets heavier.

Should I delete system files to free up more space?

No. System files are part of your phone's operating system and deleting them can cause crashes or make your phone unusable. Stick to deleting photos, videos, apps, and cache files that you downloaded or created yourself.