Everything You Need to Know About HDR TV

It took a while, but 4K Ultra HD TV is nearly everywhere now. All of the best TVs support 4K, as do most new TV shows and movies, with the exception of traditional broadcasting—and even that is poised to make the jump (eventually). Riding alongside 4K's resolution revolution is HDR (high dynamic range), another exciting video enhancement that's arguably even more impactful to your viewing experience than 4K.

But what is HDR, and why is it so integral to getting the best out of modern TVs? It's a common misconception that HDR simply makes things brighter, but it does so much more than that. HDR's key advantage is improved contrast, providing brighter brights, darker darks, and a more expansive color palette to make everything you watch look more realistic. Not all HDR is created equal, however, and you need the proper hardware and video content to take advantage. Here's everything you need to know about HDR to get the most out of your TV time.

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What Is HDR for TVs?

Not to be confused with the camera format of the same name, HDR for TV is both a video and a hardware technology. It requires an HDR-compatible TV and an HDR content source to do its thing. As the name implies, HDR provides a more expansive (and yes, dynamic) range of contrast and colors than its predecessor, SDR (standard dynamic range). This doesn’t mean HDR video makes your TV brighter—rather, it helps to unlock your TV’s brightness potential.

At its most basic, HDR content provides a road map for your 4K HDR TV to follow. To an extent, the brighter your TV can get, the more impactful your HDR experience will be. This has its limitations, constrained by both your TV’s maximum or “peak” brightness—the brightest your TV gets in small windows and highlights—and the brightness at which the content was originally mastered.

As a general guideline, you'll want a TV with a peak brightness of at least 500 nits (a unit for measuring display brightness) to experience HDR's impact. That shouldn't be difficult, considering that even budget TVs these days regularly meet or surpass that level. That said, HDR's impact is also highly affected by your TV's total contrast, the difference between the brightest and darkest images. For example, HDR content on an OLED TV that provides perfect black levels will look more impactful than on a brighter LED TV with poor black levels and contrast.

Unlike with SDR content, your HDR TV’s lighting system will be set at full power when viewing HDR content. That’s because video mastered in HDR provides more information to your TV by better adhering to the creator’s intent, so you won't just be blasted with brightness. Instead, HDR video is designed to take full advantage of what your HDR TV can do, coaxing darker black levels and richer shadow detail, brighter and more intense highlights, and more expressive colors thanks to its higher “range” of contrast and color shading than SDR video.

HDR Formats: HDR10, Dolby Vision, HDR10+

HDR comes in a variety of formats, from the basic open-source version, HDR10, to the one you've probably heard most about, Dolby Vision. Every HDR TV and content source supports HDR10, so even if you’re watching an HDR video in a format your TV doesn’t support, you’ll still reap the benefits of HDR. The biggest difference comes down to how the HDR metadata is implemented.

HDR10 is a “static” HDR format, meaning it sets the HDR range for your TV to follow at the outset and doesn't change. Dolby Vision, on the other hand, is a dynamic format that can adjust a compatible TV's HDR road map on the fly for a more finely tuned performance from scene to scene or even frame by frame. Dolby Vision video usually generates its own picture mode on your TV, one that's often more constrained than other formats due to Dolby's specifications. You’ll hear a lot about Dolby Vision's superiority over other formats, and it's the most prevalent dynamic format on most streaming services right now.

Some TVs, like those made by Samsung, don't support Dolby Vision. Samsung, Panasonic, and 20th Century Fox created their own dynamic HDR format called HDR10+ which, unlike Dolby Vision, is royalty-free. Like its cousin, HDR10+ provides a compatible HDR TV with more finely tuned contrast and color adjustments when viewing supported content than standard HDR10.

All things being equal, you're unlikely to see a major performance difference between the two formats right now. Both support the highest peak brightness and color bit depth of the current TV pipeline, at 4,000 nits and 10-bits respectively (more on that below). Dolby advertises support for up to 10,000 nits peak brightness and 12-bit color depth, but since you won't find much (if any) supported content for those specs, any major differences are mostly theoretical at present. The biggest HDR performance boost is more likely to come from the quality of your TV panel and its internal processing. Even basic HDR10 content will look leaps and bounds better than similar SDR content on a great TV.

One other HDR format to know is HLG (Hybrid-log Gamma). Developed by the BBC and NHK, this format is royalty-free like HDR10 and HDR10+. It was developed for broadcast TV and is designed to be backward compatible with SDR TVs. Because you'll rarely find HDR broadcasts in the US right now this format is rare, but like HDR10, it's supported by virtually all HDR TVs.

What Is Wide Color Gamut?

Alongside enhanced resolution, modern 4K HDR TVs allow for more expansive color shading and a higher color bit depth. Where previous displays maxed out around 16.77 million color hues (8-bit depth), today's best TVs can display up to 1.07 billion hues (10-bit depth), also called Wide Color Gamut (WCG). HDR can enhance WCG, as its higher luminance range provides a better display of the full range of colors available in the current TV ecosystem.

WCG's expanded color spectrum is measured using more advanced display color standards than the previous Rec. 709 standard. These currently include DCI-P3 and the superior BT.2020 (aka Rec 2020), which covers an even wider color space than DCI-P3. It can all get pretty complicated, but the bottom line is, with better brightness and contrast comes the ability to display a higher range of colors. The closer a 4K HDR TV or display gets to producing the full spectrum of the BT.2020 standard, the more vivid and realistic its colors will look.

Along with richer and more expressive colors, today's best HDR TVs allow for more intricate shading between colors with WCG content. This allows for images that look more like what we see in real life with less “banding” or visible distortion between color hues. Banding is especially noticeable in images like a fiery sunset or a brightly colored object against a dark background. Banding is still relatively common in HDR, especially with compressed streaming video or lower-quality TVs. You'll get the best colors, contrast, and overall HDR quality from 4K HDR Blu-rays or video files from services like Sony Pictures Core.

Where Can I Find HDR Content?

HDR is now available in a ton of places, from streaming services like Netflix, Disney Plus, Max, and Amazon Prime to games on systems like the PlayStation 5, the Xbox Series X and S, and PCs. HDR video is often bundled with 4K resolution, but that's not always the case, especially for live broadcasts. Amazon Prime's Thursday Night Football, for instance, is broadcast in HDR but its resolution is currently constrained to 1080p HD likely due to the challenges of 4K video file sizes.

While 4K HDR Blu-rays provide the best HDR experience right now, it's not clear for how much longer. You can find virtually every new film on 4K HDR Blu-ray, some of which (like Mad Max: Fury Road) push HDR to its current limits, but Blu-ray players are becoming increasingly less common. Only a few brands still sell them in the US, including Sony and Panasonic, which makes some of our favorite models. For testing purposes, we use Panasonic's DP-UB820-K and the fancier DP-UB9000, in part because they support all major Blu-ray HDR formats.

However you get your HDR, it's well worth the upgrade. From deeper and more impactful contrast to vastly superior color shading, high dynamic range is arguably the most exciting element in modern display technology, allowing for a more natural and immersive viewing experience. As we move into the next stage of display innovation, from the way video is shot and mastered to the panels on which it's displayed, HDR will help lead the way. And its future is only getting brighter.