Note: Some versions of the smartphone's built-in Gallery App may also delete the backup copy, so before deleting synced photos using the Gallery App, test to make sure it doesn't also delete the cloud backup photo.
When your camera or other device takes many photos it can run low on Memory. Google Photos provides a way to free up memory space by deleting these redundant already backed up photos while still allowing you to see the backup copy of the photo.
This FAQ discusses how to ensure that all device photos have been backed up, and shows you several methods of deleting these device photos while preserving the backup copy in Google Photos cloud storage.
Note: This works only on Android devices, iOS devices don't have the Device Folders menu item
It is important to note that if the device copy has been deleted, and the cloud copy is still in the cloud, Google Photos will show you the cloud copy of any photos that are in Google Photos but not on the device. The result is that you see the device copy - if there is one; otherwise, you see the cloud copy. This is how you see all the photos you have taken, whether or not they are still on the device. In fact, you see all the photos in Google Photos even if not taken by that device.
Ensure that photos have been backed up to Google Photos:
View your photos on a computer or web browser at https://photos.google.com/ and sign in with the same Google account you use on your phone - you will see all of your pictures there.
Compare these backed up photos to the device copy of the photos.
If the device photos all have backup copies in Google Photos, it is now safe to delete the device copy from your phone.
To see only the photos that are actually on the device (the Device Photos):
Start Google Photos and tap the menu button in the top left to get the menu
In the menu, tap on "Device Folders"
You will see the Camera folder and any other folders containing photos that are being watched by Google Photos.
If there are no Photos in the device folders, they were all deleted either by being sent to trash in which case they were not backed up, or they were backed up and deleted by the Delete Device Copy or Free Up Space tools.
In Device Folders you can select photos and go to the 3-dot menu in the upper right. In that menu you can select "Back up now" to back up any selected photos that haven't been synced, or you can select "Delete device copy" to delete the device copy if it has been synced.
Another way to see only the photos that are on the device is by using the Gallery App on the device, because it will only show photos that are on the device. Note that Gallery does not indicate whether a device photo has been backed up, so deleting a device photo using Gallery will delete the photo even if it is not backed up.
This method will delete the selected Device Photos and will prevent your backup photo from being deleted.
Open the Google Photos app on your mobile device
Select one or more photos that are on the device.
At the top right, tap on the "3 dots" menu icon.
Select Delete Device Copy.
The selected photos will be deleted from your phone, but the the Google Photos photo will remain.
Note: This works only on Android devices. iOS devices don't have the Device Folders menu item
This method will delete the selected Device Photos and will prevent your backup photo from being deleted. Only Device Folder photos are visible.
Open the Google Photos app on your mobile device
Tap "Library"
Tap on Device Folders to see all folders that have photos on the device.
Select one or more photos that are on the device.
At the top right, tap on the "3 dots" menu icon.
Select Delete Device Copy.
The selected photos will be deleted from your phone, but the Google Photos photo will remain.
This method will delete all device photos that are on your device which have been successfully backed up to Google Photos
Open the Google Photos app on your mobile device
At the top right, tap your profile photo or initial
Select Free up storage. The result will be that all device photos that have been backed up will be deleted from the device but remain in Google Photos.
Do "Check device copy status" above if you wish to handle any device copies that are not backed up and therefore were not deleted.
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