2015 iMac 21.5" 2.8GHz Quad-Core 8GB 1TB (MK442LL/A)

The 2015 iMac features one of best displays, paired with high-performance processors, graphics, and storage — all within an incredibly thin, seamless enclosure. It delivers such spectacular image quality that everything else around you seems to disappear. This version packs in a 5th generation 2.8GHz quad-core Intel Core i5 processor with 8GB of onboard memory, a 1TB hard drive, and a brilliant 1920-by-1080 pixel LED-backlit display. Adding up to the most immersive iMac experience yet — and another big, beautiful step forward.


Captivating Retina Display
Every millimeter of the Retina display was designed, engineered, and built to the most exacting standards. Something that 14.7 million pixels makes exceedingly clear. As does a 1.4 mm thin display panel designed around the human eye — so every interaction feels as natural as can be. It’s that attention to detail that inspired the all-new 21.5‑inch iMac with Retina 4K display. And just like the Retina 5K display, it delivers a larger color palette with more accuracy.

Many of the brilliant, unique colors you see in the real world never make it to your screen. A wider color gamut makes more of these real-life colors available on the Retina display. A striking 25 percent more. So whether it’s a sunset at the beach or your favorite football team’s jerseys, you’ll see them just as you saw them — on a display that’s more vibrant than ever.


Incredibly Thin, Seamless Design
The first iMac was a revolution: An all-in-one computer that put everything — display, processor, graphics, storage, memory, and more — inside one simple, stylish enclosure. Today’s iMac includes the most advanced, most brilliant desktop display Apple has ever built, and it’s filled with the latest high-performance technologies. Yet it’s still just 5 mm thin at its edge.

One of the biggest challenges Apple engineers faced with the iMac enclosure was how to join the front to the back. The enclosure is so thin, it’s not possible to weld the pieces using traditional methods. So they utilized a process called friction‑stir welding. It combines intense friction-generated heat and pressure to intermix the molecules of the two aluminum surfaces — creating a seamless, precise, and incredibly strong bond. 


Ultimate Processing Power
A fifth-generation Intel Core processor in the 21.5-inch iMac, you couldn’t ask for more speed. Yet Turbo Boost 2.0 gives you even more when you’re using processor-intensive applications like Logic Pro or Final Cut Pro. It all takes place behind the scenes, but you’ll see the difference in performance. The 21.5-inch iMac with Retina 4K display also lights up with enhanced Intel Iris Pro Graphics delivering visual effects and 3D graphics that exhibit raw power in its most polished form.


Blazing-fast Data Transfer
Each of the two ultrafast, ultraflexible Thunderbolt 2 ports significantly expand the capabilities of iMac. For example, you can connect high-performance peripherals and move data up to 40 times faster than with USB 2, and up to 25 times faster than with FireWire 800. You also have more than enough bandwidth — up to 20 Gbps — to daisy-chain multiple high-speed devices and still maintain maximum throughput.

Up To Three Times Faster Wi‑Fi
With three-stream 802.11ac technology, iMac takes desktop Wi-Fi to unprecedented speeds. Simply connect to an 802.11ac base station — such as AirPort Extreme or AirPort Time Capsule — and reach data rates of up to 1.3 Gbps.3 That’s triple the previous 802.11n standard. You also get double the channel bandwidth, with 80MHz-wide channels providing more room for more data to flow faster than ever.