Unfortunately, there is no automatic step to remove duplicate photos from Google Photos. However, by following the instructions in this article, you can find and remove duplicate photos manually, either through the Google Photos website or the mobile app. Keep in mind that Google Photos has a built-in duplicate prevention feature so if duplicate photos show up in Google Photos, there's a good chance they're due to you also backing up the photos in question to Google Drive.
Step
Method 1 of 2: Via Desktop Site
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Step 1. Open Google Photos
Visit https://photos.google.com through your computer's web browser. The Google Photos page will appear if you're already signed in to your account.
If not, click " GO TO GOOGLE PHOTOS ” and log in using your Google account email address and password.
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Step 2. Click the Photos tab
This tab is on the left side of the page. Once clicked, a list of all photos will be displayed.
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Step 3. Find duplicate photos
Swipe until you find the duplicate photo you want to delete.
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Step 4. Mark the photo box
Hover over the photo preview icon, then click the check mark in the top-left corner of the icon.
Be careful not to select both photos in duplicate pairs
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Step 5. Click the "Trash" icon
It's in the top-right corner of the page. You may see a confirmation pop-up window asking if you want to move the photos to the trash.
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Step 6. Click MOVE TO TRASH when prompted
Photos will be moved to the trash and stored for 60 days (in case at any time you make a mistake and want to undelete).
Method 2 of 2: Via Mobile Device
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Step 1. Open Google Photos
Tap the Google Photos app icon, which looks like a green, yellow, red, and blue flower.
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Step 2. Touch Photos
This option is at the bottom of the screen.
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Step 3. Touch
It's in the upper-right corner of the screen. A drop-down menu will appear after that.
On iPhone, touch the “ ⋯ ”.
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Step 4. Touch Select
This option is in the drop-down menu. After that, you can select photos.
On iPhone, touch the option “ Select photos ”.
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Step 5. Touch each photo you want to delete
When you touch a photo, the circle in the top-left corner of the photo will turn into a check mark.
Be careful not to select both photos in duplicate pairs
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Step 6. Touch the “Trash” icon
It's in the upper-right corner of the screen.
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Step 7. Touch MOVE TO TRASH when prompted
After that, the selected photos will be moved to the “Trash” folder. After 60 days, the photos will be deleted automatically.