What Is a Retina Display?

Apple's Retina display makes everything look crisper

iPad Pro
Apple

Retina display is the name Apple gave to the high-resolution screen technology it uses on various models of the iPhone, iPod touch, iPad, and other Apple products. It was introduced with the iPhone 4 in June 2010.

What Is a Retina Display?

Retina display gets its name from Apple's claim that screens made using the technology are so sharp and high quality that it's impossible for the human eye to distinguish individual pixels. A Retina display smooths the jagged edges of the pixels that make up images on screens and makes images seem more natural. 

The benefits of the technology are visible in many uses but particularly for displaying text, where the curved edges of fonts are substantially smoother than on previous display technologies.

A Retina display's high-quality images are the result of several factors:

  • A high density of pixels make up the device screen.
  • A high contrast ratio creates brighter whites and deeper blacks.
  • In-plane switching technology improves the angles from which the screen can be viewed.
  • Chemically-treated glass over the screen and LED backlighting improve the quality of the image.

The Two Factors That Make a Retina Display Screen 

There is no single screen resolution that makes a screen a Retina display. For example, not every device with a resolution of 960-by-640 pixels has a Retina display, even though that's the resolution of the iPhone 4, which has a Retina display screen. Instead, two factors create a Retina display screen: pixel density and the distance from which the user views the screen.

Pixel Density

Pixel density refers to how tightly packed the screen's pixels are — the greater the density, the smoother the images. Pixel density is measured in pixels per inch (PPI), which indicates how many pixels are present in one square inch of screen. This metric is based on a combination of the device's resolution and its physical size.

The iPhone 4 had 326 PPI due to a 3.5-inch screen with a 960-by-640 resolution. This spec was the original PPI for Retina display screens, though that value changed as later models were released. For example, the iPad Air 2 has a 2048-by-1536 pixel screen, resulting in 264 PPI. That, too, is a Retina display screen. This is where the second factor comes in.

Viewing Distance

Viewing distance refers to how far away users typically hold the device from their faces. For example, the iPhone is usually held relatively close to the user's face, while a MacBook Pro display is seen from farther away.

This distance matters because the defining characteristic of a Retina display is that the human eye can't distinguish the pixels. Something that's seen up close needs a greater pixel density for the eye not to see the pixels. Pixel density can be lower for displays viewed at a greater distance.

Other Retina Display Names

As Apple introduced new devices, screen sizes, and pixel densities and made improvements to the display technology, the company began to use other names for different Retina displays. These include:

  • Retina display: Used on the iPhone 4, among others.
  • Retina HD display: Used on the iPhone 6 Plus and others.
  • Retina 4K display: Used on the 21-inch iMac.
  • Retina 5K display: Used on the 27-inch iMac.
  • Super Retina HD display: Used on the iPhone X and iPhone XS.
  • Liquid Retina HD display: Used on the iPhone XR.

Apple Products With Retina Display

Retina displays are available on the following Apple products, at the following resolutions and pixel densities:

iPhone

  Screen Size* Resolution PPI
iPhone XR 6.1 1792 x 898 326
iPhone XS Max 6.5 2688 x 1242 458
iPhone X & XS 5.8 2436 x 1125 458
iPhone 7 Plus & 8 Plus 5.5 1920 x 1080 401
iPhone 7 & 8 4.7 1334 x 750 326
iPhone SE 4 1136 × 640 326
iPhone 6 Plus & 6S Plus 5.5 1920 × 1080 401
iPhone 6S & 6 4.7 1334 × 750 326
iPhone 5S, 5C, & 5 4 1136 × 640 326
iPhone 4S & 4 3.5 960 × 640 326

* in inches for all charts

iPod Touch

  Screen Size Resolution PPI
7th Gen. iPod touch 4 1136 x 640 326
6th Gen. iPod touch 4 1136 × 640 326
5th Gen. iPod touch 4 1136 × 640 326
4th Gen. iPod touch 3.5 960 × 640 326

iPad

  Screen Size Resolution PPI
iPad Pro 11 2388 x 1668 264
iPad Pro 9.7 2048 x 2048 264
iPad Pro 10.5 2224 x 1668 264
iPad Pro 12.9 2732 × 2048 264
iPad Air & Air 2 9.7 2048 × 1536 264
iPad 4 & 3 9.7 2048 × 1536 264
iPad mini 2, 3, and 4 7.9 2048 × 1536 326

Apple Watch

Screen Size Resolution PPI
Series 4 - 44mm body 1.5 368 × 448 345
Series 4 - 40mm body 1.5 324 × 394 345
Series 3 and earlier - 42mm body 1.5 312 × 390 303
Series 3 and earlier - 38mm body 1.32 272 × 340 303

iMac

  Screen Size Resolution PPI
Pro 5K 27 5120 x 2880 218
Pro 27 5120 × 2880 218
with Retina Display 27 5120 × 2880 218
with Retina Display 21.5 4096 × 2304 219

MacBook Pro

  Screen Size Resolution PPI
3rd Gen. 15.4 2880 × 1800 220
3rd Gen. 13.3 2560 × 1600 227

MacBook

  Screen Size Resolution PPI
Air 13.3 2560 x 1600 227
2017 model 12 2304 × 1440 226
2015 model 12 2304 × 1440 226