Every Facebook profile photo, no matter the initial size, ends up in a square box. The box is 160 pixels high on your Timeline and 50 pixels high elsewhere, and Facebook chooses part of the larger photo for this square thumbnail by default. You can also shrink the larger photo, displaying the entire image within the box. Though the box stays the same size, the image appears smaller, and Facebook crops the rectangular picture into the square frame.
Log in to Facebook and open your profile page.
Hover your mouse cursor over your current profile photo and click the link labeled "Edit Profile Photo."
Click "Edit Thumbnail" to open the Edit Thumbnail dialog box.
Check the box labeled "Click to Fit" to resize the whole photo into the thumbnail box.
Click "Save" to store your existing profile photo in its resized form.
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