What is HDR? High dynamic range on TVs, monitors and phones explained

HDR, or high dynamic range, is a way of recording and displaying images with a much wider span between the darkest shadows and the brightest highlights than standard video allows. On a good HDR TV, sunlight glints on water, neon signs glow and dark scenes keep their detail instead of turning into grey mush.

The term appears on TVs, computer monitors, phones, cameras and games consoles, and it does not always mean the same thing. This guide explains what HDR is, how the main formats differ, what brightness figures really mean, and how to make sure you actually see the benefit.

What is HDR and how is it different from SDR?

Dynamic range is the difference between the darkest and brightest parts of an image. Standard dynamic range (SDR) video was designed around the limits of old tube televisions and is mastered for a peak brightness of roughly 100 nits. HDR video can carry highlights mastered at 1,000 nits and above, with the signal format itself allowing up to 10,000 nits.

HDR is usually paired with two other upgrades. A wide colour gamut lets the picture show deeper, more saturated reds and greens than SDR. A higher bit depth, typically 10-bit instead of 8-bit, allows over a billion shades instead of about 16.7 million, which reduces visible banding in skies and gradients.

HDR is separate from resolution. 4K describes how many pixels a screen has; HDR describes how bright, dark and colourful each of those pixels can be. Most 4K content from streaming services and discs is also available in HDR, which is why the two are often sold together.

HDR formats explained: HDR10, HDR10+, Dolby Vision and HLG

Several HDR formats exist, and a TV or monitor lists the ones it supports. The main difference is metadata, the extra information that tells the screen how to display each scene.

• HDR10: the baseline, royalty-free format supported by virtually every HDR device. It uses static metadata, meaning one set of instructions for the whole film.
• HDR10+: adds dynamic metadata, so brightness can be adjusted scene by scene or even frame by frame. It is royalty-free and supported by many TVs and some streaming services.
• Dolby Vision: a licensed format with dynamic metadata and support for up to 12-bit colour. It is widely used by streaming services, discs and some phones.
• HLG (Hybrid Log-Gamma): developed by the BBC and NHK for live broadcasting. It needs no metadata and is designed so that one signal looks acceptable on both HDR and SDR screens.

Accepting an HDR signal and displaying it well are two very different things.

Does the HDR format matter?

Dynamic metadata matters most on screens that cannot reach the brightness the film was mastered for. Instead of applying one compromise to the whole film, the TV gets guidance for each scene, so a dark cave and a bright desert are both handled sensibly. On a very capable display, the difference between formats is smaller.

In practice, the quality of the screen itself matters far more than the logo on the box. A bright TV with good contrast showing HDR10 will usually look better than a dim budget set that supports every format. If you watch a lot of streaming content, support for both Dolby Vision and HDR10+ avoids any gaps, but it should not be the deciding factor.

What makes a good HDR display?

Accepting an HDR signal and displaying it well are two very different things. Many cheaper TVs and monitors carry an HDR label but lack the brightness or contrast to show a real difference.

• Peak brightness: measured in nits (candelas per square metre). Highlights benefit from 600 nits or more; very bright sets exceed 1,000 nits.
• Contrast and black level: OLED screens switch off individual pixels for true black. LCD screens with local dimming, especially mini-LED, dim zones of the backlight to improve contrast.
• Colour gamut: look for high coverage of the DCI-P3 colour space, which most HDR content is mastered in.
• Certification on monitors: the VESA DisplayHDR tiers (for example 400, 600 and 1000, plus True Black tiers for OLED) give a tested minimum level of performance. DisplayHDR 400 is an entry level and often looks only slightly better than SDR.

Why does HDR look washed out or too dark?

This is one of the most common complaints, and it usually has a simple cause. On computers, turning on HDR changes how the system displays ordinary SDR content, and on screens with limited brightness, desktop apps and web pages can look grey and flat. Many operating systems include a slider to adjust SDR brightness while HDR is active, and on basic HDR monitors it is often better to switch HDR on only for films and games.

On TVs, dim HDR is often caused by energy-saving settings, an ambient light sensor or a picture mode designed for a dark room. Try a cinema or filmmaker mode with power saving off. Also check the connection: 4K HDR at high frame rates needs a suitable HDMI port and a certified high-speed cable, and some TVs require you to enable enhanced HDMI signal settings for each input.

HDR on phones, cameras and games

The HDR mode in a phone camera is related but not identical. It combines several exposures into one photo so that bright skies and dark foregrounds both keep detail. Many modern phones can also record HDR video and display HDR photos, which appear brighter in the highlights on a compatible screen.

For games, HDR can make a big visual difference on a capable display. Consoles and many PC games include an HDR calibration screen; take a minute to set the black level and peak brightness so the game matches what your screen can do.

Is HDR worth it?

On a bright, high-contrast TV or monitor, yes. HDR is one of the most visible picture upgrades of recent years, often more noticeable than a jump in resolution from normal viewing distances. On a dim entry-level screen, the benefit is small and sometimes negative.

If you are buying a new screen for films, streaming or gaming, treat brightness, contrast and colour as the real HDR features, and the list of supported formats as a secondary check.

Frequently asked questions

HDR is a genuine step forward in picture quality, but only when the screen can do it justice. Look past the logos to brightness, contrast and colour coverage, check your picture settings and cables, and you will see what high dynamic range is meant to look like.

How we research: Guides are written from established sources and checked for accuracy. They are general information, not professional advice.