HDR can make your 4K TV look brighter and more colorful than ever - here's everything you need to know about this must-have display feature

• High Dynamic Range (HDR) enables TVs to produce better contrast, brighter images, and more colors than ever before.
• There are three main HDR formats: HDR10, HDR10+, and Dolby Vision.
• 4K TVs with HDR are available from LG, Sony, Samsung, Vizio, TCL, and more.
• You can watch HDR movies on 4K Ultra Blu-ray discs and streaming services, like Disney Plus, Amazon Prime Video, and Netflix.

With the jump from HD to 4K and now 8K, TVs have enjoyed a sharp upgrade in detail - but the number of pixels on a display is actually only one small part of what makes Ultra HD TVs look so good today. In fact, there's a display feature on most modern TVs that's arguably even more important than resolution. It's called high dynamic range (HDR).

Now, you've probably seen the letters "HDR" plastered in bold across many TV boxes, and perhaps you've wondered what this home theater buzzword really means. While there are plenty of fun tech details to get into for those who want a full breakdown, the main gist of HDR really couldn't be any simpler - it allows TVs to produce images with higher brightness, better contrast, and more colors than ever.

In other words, HDR can make images truly pop and appear more realistic and closer to how content creators intended for them to look.

But, while HDR is generally a must-have feature to have on any new 4K TV, performance can vary wildly across different display models. There are also a few competing HDR formats that can cause confusion for some buyers who might not be aware of their differences. With all that in mind, we've put together a handy guide detailing all the ins and outs of HDR.

What is HDR?

HDR is an image technology featured on many 4K Ultra HD TVs, 4K Blu-ray discs, and 4K streaming titles.

Before 2015, basically all TVs and digital content were produced for standard dynamic range (SDR) playback. This restricted them to displaying a limited scope of colors and brightness. HDR expands that previous range significantly, allowing creators to master videos with enhanced contrast and a wider array of colors. Similarly, TV manufacturers can now make displays capable of playing these special HDR videos in all their glory.

In practice, this means that when you watch HDR videos on an HDR TV you can enjoy an added sense of color and depth with more visible details and intensity in bright highlights and dark shadows. A good example would be a scene featuring sunlight glimmering off of the ocean. In SDR, a sequence like this might look dull with lost detail - but with the expanded range that HDR allows, extreme highlights like this are given room to breathe and really pop. In other words, the reflecting light can look both brighter and more detailed in HDR compared to SDR.

Brightness levels for HDR are measured in a unit called nits. The more nits a TV can produce, the brighter the display's HDR highlights will look. In general, most HDR movies and TV shows are mastered with a max of 1,000 to 4,000 nits in mind, though certain HDR formats can be mastered for up to a whopping 10,000 nits.

Meanwhile, when it comes to color, HDR videos are mastered within a wide color space or gamut known as Rec. 2020 - though most HDR movies and TV shows are actually produced for the DCI-P3 gamut. The latter is the same range of colors used for digital theaters, while the former supports an even wider range than that. So, with HDR you can now enjoy the full spectrum of colors you see in theaters at home. This was something that was previously impossible on SDR TVs.

Together, the enhanced contrast and color of HDR complement each other to create a more realistic, bold, and impressive sense of depth and saturation - giving HDR TVs a clear visual upgrade over SDR displays.

How do I watch HDR movies and TV shows?

In order to watch HDR videos, you'll need an HDR-capable TV and access to HDR content.

Most new Ultra HD TVs include some level of support for HDR, but performance can vary dramatically between cheaper models and more expensive displays. If you want to get the best HDR performance, you'll want to pay close attention to two main specifications when choosing a TV: peak brightness and color gamut coverage.

When it comes to brightness, you'll want to find a TV that can come close to outputting 1,000 nits or higher to really see the full benefits of HDR. TVs with that level or performance tend to be a bit pricey, however, and cheaper displays in the 400 to 600 nits range can still offer worthwhile HDR playback, too.

For color gamut, you'll want to find a TV with at least 90% coverage of the DCI-P3 color space. The closer to 100%, the better, of course, but displays with high specifications like that are more expensive.

On the more affordable end, we recommend the TCL 6 Series and Vizio M Series Quantum as ideal entry-level HDR TVs. For those with the cash to spare, flagship sets like the LG C9 OLED and Samsung Q90R QLED will provide even better HDR performance.

Once you have an HDR-capable TV, you'll need to find some HDR videos to actually play on it. Thankfully, there's a growing collection of HDR movies and TV shows available on several streaming services, including Disney Plus, Netflix, and Amazon Prime Video. Most 4K HDR TVs include built-in access to these apps right through their smart TV interfaces, so all you have to do is log in to stream HDR videos.

If there's a particular 4K HDR app missing from your smart TV, or your display's interface is lacking, you can also opt for a standalone 4K HDR media player like the Roku Ultra, Amazon Fire TV Stick 4K, and the Apple TV 4K. Remember, in this case both your TV and your set-top box need to support 4K HDR playback to see the effects.

Finally, if you want the best quality 4K HDR playback, you can get a 4K Ultra HD Blu-ray player to watch 4K Ultra HD Blu-ray discs with HDR support. These 4K Ultra HD Blu-ray players are available from manufacturers like Sony, LG, and Panasonic, and again require a TV that supports 4K HDR to get the full effect.

Are there different HDR formats?

There are three primary HDR formats: HDR10, HDR10+, and Dolby Vision.

HDR10 is the most basic and common HDR format. It's supported on all 4K HDR TVs and is used as the standard HDR format on all 4K Ultra HD Blu-ray discs and streaming apps with HDR content. In other words, you can think of it like an HDR base layer that more advanced HDR formats can be added on top of.

HDR10 videos are encoded with information called "static metadata." Basically, this metadata tells a TV what colors to show and how bright the TV's images are supposed to look, helping the display to scale its HDR playback to match its own capabilities. Static metadata is a bit limited, however, as it can only provide information that addresses the video as a whole, instead of each individual scene.

In practice, this can lead to some issues with certain scenes in HDR10 videos appearing too dark or blown out on entry-level and mid-range HDR TVs. Thankfully, there are two other HDR formats that have been designed to help remedy this problem - Dolby Vision and HDR10+.

Dolby Vision and HDR10+ are both "dynamic metadata" HDR formats. This means that HDR brightness and color information can be detailed on a scene-by-scene or even shot-by-shot basis. As a result, Dolby Vision and HDR10+ videos can be scaled more accurately to match the specific capabilities of your HDR TV. This can provide a better HDR viewing experience on less expensive TVs.

While Dolby Vision and HDR10+ both offer the same primary benefit over standard HDR10, device and content support for each format differs quite a bit.

When it comes to displays available for purchase right now in the US, HDR10+ is currently only available on TVs from Samsung and Vizio. Meanwhile, Dolby Vision is supported on TVs from Vizio, LG, Sony, TCL, Hisense, and Toshiba.

Dolby Vision support is also available on more streaming players, including the Apple TV 4K, Nvidia Shield TV Pro, Fire TV Stick 4K, and Fire Cube. HDR10+, meanwhile, is only supported by the Fire TV Stick 4K and Fire Cube.

When it comes to content, Dolby Vision movies and TV shows are also much more common than HDR10+. Dolby Vision streaming titles are available on Netflix, Disney Plus, Apple TV, Vudu, and Amazon Prime Video. HDR10+ videos, on the other hand, are only currently streaming through Amazon Prime Video. More 4K Ultra HD Blu-ray discs support Dolby Vision as well, but there is growing support for HDR10+ discs from studios like 20th Century Fox, Warner Brothers, and Universal.

Ultimately, all three formats provide fairly similar performance, and no matter what HDR hardware you have or HDR content you're watching, standard HDR10 support will always be included.

For more 4K HDR TV and 4K HDR device recommendations, check out our various buying guides:

• Best 4K TVs
• Best affordable 4K TVs
• Best OLED TVs
• Best streaming media streaming sticks and devices
• Best 4K Ultra HD Blu-ray players

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