This article teaches how to set an image as a cover photo on Google Photos using a desktop browser.
Steps
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Step 1. Open the Google Photos site in a browser
Type photos.google.com in the browser address bar, then press Enter on your keyboard.
If the login is not automatic, click on "Go to Google Photos" and log into your account
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Step 2. Click the Album button
The icon (
) is on the left side of the page. A list of all saved photo and video albums will open.
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Step 3. Click on an album
Search for the album you want to edit and open it to view its contents.
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Step 4. Click on the image you want to use as a cover
Scroll down to see all the photos in the album, then click on the one you want to use to open it in full screen.
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Step 5. Click on the ⋮ icon
It is located at the top right and opens a drop-down menu with various options.
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Step 6. Click Use as Cover Image in the menu
The selected image will then be set as the cover photo.