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When you access your photos, you've surely noticed that they appear in order by date and time. You can rearrange the order of these photos by changing their dates and times. You'll need access to a computer. To rearrange the photos in an album instead, see Rearranging Photos in an Album. If you're not already signed in to Google Photos, do so now. A selection circle will appear at the photo's top left corner. A check mark will fill the circle. You can select multiple photos to change all to the same date and time. Just click the circles on each photo you want to edit. A brief menu will appear. " Now you'll see the "Edit date and time" pop-up. The photo's current date and time information is visible on this window. To move the photo closer to the top of the list, make the date later than the current one. To move the photo downward, make the date earlier. " Your photos will now be reordered based on the edited time and date.
Open http://photos.google.com in a web browser. Hold the mouse cursor over a photo. Click the circle to select the photo. Click the icon at the upper right corner. Select "Edit Date & Time. Replace the current date and time with a new one. Click "Save.