The iPad Air Wallpaper size (1640×2360px)
1640x2360 pixels is the native portrait resolution of the iPad Air, a roughly 41:59 Liquid Retina display. A wallpaper at this exact size fills the panel edge to edge with no upscaling, keeping photos and artwork crisp on the iPad Air's bright, high-quality screen used across the Home Screen and lock screen.
The iPad Air's ratio is close to but not exactly 3:4, and like every iPad it rotates, so a wallpaper needs to look right in both portrait and landscape. That combination is why phone and desktop wallpapers never sit well on an iPad; resizing to the native 1640x2360 gives iPadOS exactly the portrait canvas it expects while keeping your composition undistorted.
Because the panel is large and Retina-sharp, use a good high-resolution source at or above 1640x2360 so detail holds up when scaled to the tablet; a small image will look soft. Plan for the interface: the lock screen shows a large clock in the upper-middle, and the Home Screen lays out a grid of app icons and widgets. Keep the focal point centered so it survives rotation and reads well behind the icon grid, and treat the edges as areas that may be covered by dock and widgets. This tool resizes entirely in your browser, so your file is never uploaded, it is free, and your original quality is preserved while the image is fit to the 41:59 iPad Air frame. Apple can change specs, so verify before exporting.