What is the pixel or inches dimension to create a perfect sized wallpaper in Photoshop for the iPad air?

I figured out by trying different sizes to make about a perfect sized wallpaper for the iPhone 5, but can't seem to make one for the iPad air. The dementions I used for the iPhone 5 was 1536x 894 pixels or (12.417 inches Wide x 21.333 inches Height) which fits the iphones wallpaper about perfect. Note this is with having reduce motion ON in the settings>accessibility tab. I used photoshop to create these wallpapers. Please let me know if you have figured this out Thanks!