sizing facebook photo to fit on mac laptop

Hi, and welcome to TSG.

1) The current dimensions for Facebook cover photos are 851 pixels wide and 315 pixels tall for the desktop version of Facebook and 640 pixels wide by 360 pixels tall for the mobile version. Which version is your cover photo?

2) What is the exact resolution (in pixels) of your Mac laptop screen?

3) What do you mean by "appear full size"?

4) What picture manipulating software do you have available to work with?

 

Allow me to make one correction to my first post. The current size of a Facebook cover photo is 820 x 312 pixels.

I have no idea what you are trying to do. Your first post makes it sound like there is a cover photo on some Facebook page that you wish to download FROM Facebook to your Mac laptop and then manipulate it so that it appears full size, in some manner on your Mac laptop. Your second post says you want to download a picture TO Facebook. Copying files from one's computer to some website is typically referred to as Uploading. Copying files from some website to one's computer is typically referred to as Downloading.

Are you attempting to Upload a picture from your Mac laptop TO Facebook to use as a cover photo? Is that photo 650 X 400 pixels in size? Do you want the full photo to appear in the desktop version of Facebook or the mobile version? A photo properly scaled for the desktop version will appear to have the sides chopped off when scaled in the mobile version. A photo properly scaled for the mobile version will appear to have the top and bottom chopped off when viewed in the desktop version. There is no way to get around that.

 

From what I am reading online, the Tools -> Adjust Size menu selection will allow you to scale your picture to any desired number of horizontal and vertical pixels. The picture will distort (round circles will appear elliptical, for example) if you scale by different percentages in the horizontal and vertical directions. None of the overall view of the picture is lost when the size is adjusted.

If you want your photo to always appear in its entirety, no matter if viewed on a desktop or mobile device, you will need to live with the fact that you need to add areas of border pixels to the photo so that you may end up with the border pixels showing on both sides when viewed on a desktop and top and bottom when viewed on a mobile device. This way, the only thing that Facebook will be cropping is the border pixels and not the actual picture portion. I don't know if the Mac Preview application allows one to easily add such border pixels.

If you prefer, upload your original jpeg picture file in your reply (there should be an Upload a File button below your post's text entry box, tell me the color you wish for the border pixels, and also tell me if you want the photo to be uncropped in both the desktop and mobile views or just either the mobile or desktop view. I will add the border for you and upload the results.