When designing responsive websites it pays to know the various resolutions so you can create proper breakpoints in your design. Apple Apple Ipad 2 – 1024 x 768 at at 132 ppi with a 9.7 inch display Apple Ipad with Retina display – 2048-x 1536 at 264 ppi with 9.7 inch display Apple Mini – 1024 x 768 at 153 ppi with a 7.9 inch display Apple IPod – 1136 x 640 at 326 ppi Apple IPod -4th generation – 960 x 640 at 320ppi Apple Ipod Touch – 1136 x 640 at 326 ppi Apple IPhone 4 and 4S – 960 x 640 at 326 ppi with a 3.5″ display Apple IPhone 5 – 1136 x 640 at 326 ppi with a 4″ display Amazon Kindle Kindle Fire (1st gen) 1024 x 600 with 7″ display Kindle Fire (2nd gen) 1024 x 600 with 7″ display Kindle Fire HD 7″ – 1280 x 800 with 7″ display Kindle Fire 8.9 – 1920 x 1200 with 8.9″ display Android Phones Samsung Galaxy II – 800 x 480 at 218 ppi Samsung Galaxy III – 1280 x 720 at 306 ppi Blackberry 10 – 1280 x 768 Blackberry Z10 – 1280 x 768 Android Tablets Samsung Galaxy Tab 10 – 1280 x 800 – 10″ display Samsung Galaxy Tab 7 and 7 Plus – 1024 x 600 – 7″ display Acer Iconia Tab A500 – 1280 x 800 – 10″ display It seems to me without getting into a whole bunch more models, and older phones the breakpoints at minimum should be 1280, 1024, 800, 600, 480 and 320. Of course it really all depends on the final design. And to even further the matter more their is a whole genre being created about fluid grids. Articles to Use as a Reference for further exploration: .Net Magazine – determining breakpoints for a responsive design 1st WebDesigner – overview of breakpoints in responsive design Device-Agnostic Approach to Responsive design Webdesignerwall – Setting Breakpoints in Responsive Design Wikipedia’s list of display’s by pixel density And of course Ethan Marcotte, who we can thank for starting the whole responsive web idea.