How to quickly know the dimensions of an image? I am looking for a nice and quick way to display the dimension of an image from OS X 10.9. Presently, I have to open the image in photoshop and then enter a menu to know the dimensions. The process is too slow when I have to browse through dozens of pictures and get those with dimensions big enough.
Get Info
You can get the resolution from Get Info menu. Select the image and press ⌘ CMD+i, or right click on that image and choose Get Info menu item.

Image from cultofmac.com
QuickLook plugin
If you weren't on 10.9 - this lightweight QuickLook plugin called qlImageSize which can be found on GitHub lets You check the image size on the quicklook window title. I don't have any that work on 10.9, but perhaps this will help you if you wish to search for a similar one or report 10.9 compatibility to that project for improvement.