What are hz in tvs?

Refresh rate—measured in hertz (Hz)—describes the amount of times the picture refreshes per second. To put it in the simplest terms, a display's refresh rate describes the number of times per second the display resets the image, whether you're shopping for a TV or a computer monitor.

Shopping for a new TV used to be just a matter of TV brand and screen size. These days, there’s way more to consider, like the different types of display technology, HDR support, and smart features.

One label that you’re sure to see on just about every TV box is refresh rate. It’s a hardware specification that describes how motion is handled on any given TV. Before you buy your next TV, it’s worth taking this spec into consideration—particularly if you’re an avid gamer or sports fan who watches a lot of fast-paced action. We'll help dispel the mysteries of this technology to help you make the right decision.

To put it in the simplest terms, a display’s refresh rate describes the number of times per second the display resets the image, whether you’re shopping for a TV or a computer monitor. The refresh rate is measured in Hertz (Hz).

Essentially, the higher your display's refresh rate, the less amount of time that will pass between each individual video frame being displayed on screen. Higher refresh rates mean that a TV or monitor can display more frames per second (fps) which, depending on the content it's fed, could affect how smooth and pleasing your video looks.

There are essentially two types of common refresh rates available when it comes to contemporary TVs: 60Hz and 120Hz. Generally, 60Hz TVs are more affordable than 120Hz TVs because the 120Hz spec is usually found on TVs that offer premium hardware and software features in addition to higher-quality motion handling.

In 2022, TCL and Samsung both announced TVs with a 144Hz native refresh rate. This spec has been available in some computer monitors for years, and in fact, some monitors offer native refresh rates that go much higher, up to 360Hz.

As far as TVs go, however, most people will end up choosing between 60Hz and 120Hz right now.

While the refresh rate describes the number of frames of video per second a particular TV or monitor is capable of displaying, the frame rate describes the playback speed (in seconds) of a piece of video content. The frame rate of a piece of video content will be listed in fps (frames per second). A frame rate that divides cleanly into a TV’s refresh rate will make video smoother to watch.

For example, broadcast television in the U.S. plays at a standard 30fps (actually just below this at 29.97fps), which fits nicely into a 60Hz TV's refresh rate. However, most movies are shot at 24 frames per second (fps), which was settled upon in the early days of film. This is the frame rate you'll likely see when you pop in a Blu-ray disc or a film on streaming service. If you settle in to watch a movie on Netflix, you're probably watching something at 24fps.

The problem is, the average 60Hz TV can't render native 24fps content without a little bit of help, since every three seconds the TV gets out of sync. To combat this, many modern 60Hz TVs use a telecine technique called 3:2 pulldown, where frames are doubled in alternating sequences in order to "meet up" with the display's 60Hz refresh rate. Unfortunately, 3:2 pulldown usually results in a motion artifact called judder, where some sequences during playback can have a stuttering or skipping effect.

While many modern 60Hz TVs do 3:2 pulldown so successfully that you probably won't notice the amount of judder in most scenarios, you can save yourself any trouble by purchasing a 120Hz TV. That's because 24fps divides evenly (5 times) into a 120Hz refresh rate.

In addition, if you've recently bought a next-gen gaming console, you're likely going to be displaying content at much higher frame rates than film or broadcast TV. This is where having a TV with a higher refresh rate can really pay off.

One advantage of a 120Hz TV centers around the gaming benefits touched on above. In addition to being inherently better at handling fast-paced video games, the 120Hz spec also ensures that you’ll be able to play console games that offer 120fps game modes to perfectly sync up with the ultra-fast motion and get the best out of your gaming experience.

Currently, the Xbox Series X and the PlayStation 5 are all capable of displaying 4K games at 120fps, and while there aren’t very many games yet that hit this benchmark, you can expect to see more of them in the coming years. If you're a PC gamer who wants to play on the big screen, you'll also reap the benefits from a 120Hz TV, as high frame-rate games have been available in that ecosystem for quite some time.

If you own one of these consoles but don’t own a TV with a native 120Hz refresh rate, you won’t have the best possible gaming experience at your fingertips. That's not to mention other gaming advantages that often come with premium TVs, like Variable Refresh Rate (VRR) and Auto Low Latency Mode (ALLM).

Regardless of frame rate, higher refresh rates tend to eliminate blur from fast motion, which isn’t just valuable for gaming: It also matters during high-action content, like sports. Because 120Hz TVs check for new information twice as often as 60Hz TVs, they can sometimes render particular sequences in sports with more clarity.

Ultimately, you might care more about landing a great deal on an affordable TV than you do about achieving the ultimate gaming or film experience. If you’re more of a casual viewer and sports broadcasts aren’t incredibly important to you and your family, there are plenty of budget-friendly 60Hz TVs that will fit your lifestyle perfectly.

That said, we highly recommend shopping for a 120Hz TV if you’re an avid gamer, a dedicated sports fan, or if you just want your movies and shows to look as easy on the eyes as possible. Motion handling can have a big impact on picture quality, especially for those specific content types.

All of the options in our round-up of the best gaming TVs feature a native refresh rate of 120Hz, and several of the picks in our round-up of the best TVs do, as well.

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Even though we don't see it, our TV is constantly refreshing itself every second. A refresh rate defines how many times per second it draws a new image on the screen, and it's written out in Hertz (Hz). A 60Hz refresh rate means that the screen is refreshing itself 60 times every second, and at 120Hz, it's refreshing itself 120 times every second. This is different from frame rate, which is how many times per second the source sends a new frame. So if you have a source that's displaying 60 frames per second, you always want your TV to be refreshing itself 60 times/second so that the refresh and frame rate match up, otherwise motion may look blurry.

The refresh rate affects motion handling; the more times the display can draw a new image the better it is for fast-moving content. Modern TVs either have a 60Hz or 120Hz refresh rate. Most high-end TVs have a 120Hz refresh rate, but it doesn't mean they're inherently better at motion handling either. The response time determines how good motion looks; a quick response time means that motion looks clear, while a TV with a slow response time leads to motion blur. Response time and refresh rate are indirectly related as a 120Hz panel is expected to have a better response time than a 60Hz panel, but it's not a guarantee.

Since not all content will automatically have the same frame rate as your TV's refresh rate, there are also ways a TV increases the frame rate to match up with the refresh rate, improving the appearance of motion.

A 60 fps video played on a 120Hz TV should look almost identical to the same content played on a 60Hz TV. In a case like this, the TV either adjusts itself to match the refresh rate of the source, which effectively turns it into a 60Hz TV, or it simply doubles every frame.

As you can see from the picture above, a TV with a higher refresh rate doesn't produce less motion blur. Since both of these TVs have a very similar response time, 60 fps content results in an almost identical picture.

To better showcase these differences, we compared two TVs side-by-side; a 60Hz model, and a 120Hz model, with similar response times. We filmed these TVs in slow motion to easily compare each individual frame.

While a 120Hz TV doesn't inherently produce better motion, it can provide a few advantages over standard 60Hz TVs. One of the most important advantages is the ability to play back content that is meant to be displayed at 24 fps, which is often found in movies. Most TVs can simply lower their own refresh rate to 24Hz when the content is 24 fps, but some sources, such as Chromecast, output video at 60 fps, even if the content is 24 fps. This means that the TV's refresh rate remains at 60Hz, and motion won't appear smooth, which is an effect called judder. A 60Hz TV has trouble removing 24 fps judder because 60 isn't a multiple of 24. To display this type of content, a technique known as a "3:2 pulldown" is used. Basically, 12 of the 24 frames repeat three times, while the other 12 repeat twice, totaling 60 frames. Not everybody notices this, but it causes some scenes, notably panning shots, to appear juddery. However, 120Hz TVs have an advantage here because they can simply display each frame five times since 120 is a multiple of 24.

Learn more about judder here

There are a few sources that display 120 fps, such as the Xbox Series X or the PS5, and having a 120Hz TV helps display this content at its max frame rate. While it's rare to find content other than games with this frame rate, displaying 120 fps has a significant impact on the perceived motion. As you can see in the picture below, content looks much smoother at 120 fps than at 60 fps on a 120Hz TV.

With the release of HDMI 2.1, there may be more 120 fps sources available in the coming years. This new HDMI standard allows TVs to display 4k images up to 120 fps, whereas HDMI 2.0 allows up to 60 fps. This means that 120Hz TVs may slowly become the norm.

Another place where 120Hz is useful is if you enjoy the motion interpolation feature found on TVs (also known as the Soap Opera Effect). It allows the TV to generate frames between existing ones, increasing the frame rate to match up to the refresh rate. Most TVs have this feature; a 60Hz TV can interpolate 30 fps content, while a 120Hz TV can interpolate 30 and 60 fps content. This is why a 120Hz TV is an advantage over 60Hz since it can interpolate more types of content.

There are other ways to produce a similarly clear image as a 120Hz refresh rate. Many TVs these days have a feature called Black Frame Insertion. Essentially, the TV displays a black screen between each frame, which most people can't see, but it can also make the screen dimmer. On most LED TVs, this is achieved by adjusting the flicker frequency of the backlight, which results in the backlight being turned off for half the frame. On OLED TVs, which don't have a backlight, this is done by inserting a black frame in-between each frame.

Persistence blur occurs when your eyes move past a static image, such as each static frame that makes up moving content. With Black Frame Insertion, the static frame is present for a shorter duration, so the length of the persistence blur is shorter. Unfortunately, though, not everyone can stand the flickering, and some people may get annoyed after a while.

A TV is only as good as the content you are playing, and unfortunately, very little 120 fps content actually exists. With the new HDMI 2.1 standard, gaming consoles like the Xbox Series X and PS5 support 120 fps, but there isn't much online content available at such a high frame rate. We've compiled a couple of lists of common entertainment sources as well as their respective refresh rates.

A source's frame rate isn't always constant, especially in games. It may drop and if that happens, it can lead to screen tearing because the frame rate of the game and the refresh rate of your TV don't match up. There's a feature called variable refresh rate (VRR) that aims to match the refresh and frame rate on-the-go, so if the frame rate of the game drops, the TV automatically lowers its refresh rate as well. This is only possible if both the TV and the source support VRR.

There are different formats of VRR, with AMD's FreeSync, NVIDIA's G-SYNC, and HDMI Forum VRR being the three most common types. G-SYNC is usually reserved for monitors, but some TVs are compatible with it. Higher-end Samsung and LG TVs have FreeSync, and support for HDMI Forum VRR is starting to grow on HDMI 2.1 TVs. As for compatible devices, the Xbox Series X supports FreeSync and HDMI Forum VRR, while the PS5 should receive an update in 2021 for HDMI Forum VRR.

Learn more about variable refresh rate

TV companies will often market their refresh rates in ways to make it seem like it's higher than it actually is. A company like Samsung uses the term 'Motion Rate'; the Motion Rate on a 60Hz TV is 120, while a 120Hz model has a Motion Rate of 240; they effectively double the refresh rate to come up with this number, and there's no real explanation as to why it's marketed like that. LG uses 'TruMotion', Vizio has 'Effective Refresh Rate', and Sony has two terms: 'MotionFlow XR' and 'X-Motion Clarity'. These marketing numbers don't really mean anything, and you need to check the TV's specs to find the real refresh rate.

Learn more about fake refresh rate

LCD TVs are lit by LED lights, and most TVs use Pulse Width Modulation (PWM) to dim the backlight. What this means is that the backlight turns itself off every few seconds, so it doesn't get too bright. It's not visible to the human eye because of how fast the frequency is. Flicker frequency, like refresh rate, is measured in Hz because we want to know how many times it flickers every second.

If the flicker frequency doesn't match up with the refresh or frame rates, it can create some image duplication. As you can see in the images below, motion on the LG UN8500 has image duplication because its backlight flickers at 120Hz; this is double the 60 fps source. However, the Sony X800H has a flicker-free backlight, so there's no image duplication - the motion blur is caused by a slower response time.

Refresh rate is one of the more confusing aspects of TV technology and TV makers don't do much to explain it. In fact, they often obscure it.

Refresh rate is a number that specifies how many times per second the image on your TV changes. With most TVs it's 60, though it's rare you'll ever see a TV with that number listed. Instead, manufacturers use different technologies, such as the soap opera effect and black frame insertion, to claim a higher number. Sometimes those claims are justified, sometimes they aren't.

Higher refresh rate claims with numbers like 120, 240 and higher are common, but not always accurate. In fact, no matter what number you see listed with a 4K TV, no 4K TV has a native panel refresh rate higher than 120Hz. As we'll explain, though, a number higher than 120Hz doesn't necessarily mean the claim is false.

Here's the basics:

Let me start with the terms you'll see on various TV makers' marketing materials and web sites. Each one calls the TVs motion handling capability something different, and many don't even mention the term "refresh rate" or use "Hz" at all.

LG: TruMotion

LG's web site lists the panel's native refresh rate up front. On TVs that have a 120Hz refresh rate it simply says "120Hz Native," while with 60Hz models it lists "TruMotion 120 (60Hz Native)."

Samsung: Motion Rate

Samsung is better than it used to be about this, albeit not as transparent as LG. The 4K TVs  and 8K TVs on its site list a "Motion Rate." This is, generally, twice the native refresh rate. So Motion Rate 240 indicates a native refresh of 120Hz while Motion Rate 120 means a 60Hz refresh. In the least expensive of their TVs, a Motion Rate of 60 means a 60Hz refresh.

Sony: MotionFlow XR

For most of its 2021 TVs Sony doesn't list a number on its website, instead it just says "Motionflow XR." On some, however, it lists a number along with the native refresh: "Motionflow XR 240 (native 60 Hz)" and "Motionflow XR 960 (native 120 Hz)."

Vizio: Refresh Rate

Vizio used to list an "Effective Refresh Rate" on its web site, which was just double the native refresh rate. For 2021, however, none of its TVs use that term as far as we could find, and most don't list any refresh rate spec. The bottom line? All of Vizio's 2021 TVs are 60Hz native, except for the P-Series and the H1 OLED, which are 120Hz native.

TCL: Clear Motion Index or Natural Motion

TCL's sets are all over the place. Some don't list any motion term -- those are 60Hz native. Some say "120Hz CMI," which stands for Clear Motion Index, but they're actually 60Hz native too. And some say Natural Motion 240, but they're 60Hz as well. The only TCL TVs that are true 120Hz say Natural Motion 480.

For the most effective increase in motion resolution, and compatibility with next-gen gaming consoles' best video output modes, you need a native 120Hz refresh television. That said, it is possible to have some improvement in motion resolution even with a 60Hz TV if it uses some other feature, like backlight scanning or black frame insertion, that improves motion resolution.

That's a lot of technical jargon, so let's tackle it from the beginning.

Refresh rate is how often a TV changes the image (also known as a "frame") onscreen. With traditional televisions, this was 60 times each second, or "60Hz."

Some modern TVs can refresh at double this rate, or 120Hz (120 frames per second). We've covered this before, with 1080p HDTVs, and it's the same idea with 4K TVs. Certain parts of the world have TVs that refresh at 50Hz normally, with some TVs that refresh at 100Hz. That just depends on the electricity in your country.

For the purposes of this article, 50 and 60 work the same, as do 100 and 120. For my own sanity, and ease of reading, I'm going to stick with 60 and 120, but feel free to read that as 50 and 100 if you're in the UK, Australia or any place that has 50Hz electricity.

So are these higher refresh numbers just another "more is better!" marketing ploy? Not entirely. Higher refresh rates can reduce motion blur in LCDs and OLED TVs.

What's motion blur? Glad you asked...

All LCD and current OLED models suffer from "motion blur." This is where anything in motion, either an object on screen or the entire image (like when the camera pans), blurs and looks softer than if it was stationary.

Interestingly, this blur is largely created by your brain. Basically, your brain notices the motion, and makes assumptions as to where that object (or overall image) is going to be in the next fraction of a second. The problem with LCD and current OLED TVs is that they hold that image there for the full 60th of a second, so your brain actually smears the motion, thinking it should be moving, when in fact it's just a series of still images.

It's actually quite fascinating, but the details are beyond the scope of this article. I recommend checking out BlurBuster's great article for more info.

The motion blur we're talking about here, despite coming from your brain, is caused by how the television works. This is separate from whatever blur the camera itself creates.

Some people aren't bothered by motion blur. Some don't even notice it. Others, like me, do notice it and are bothered by it. Fortunately, it can be minimized.

Refresh rate itself is really only part of the solution. Just doubling the same frames doesn't actually do much for reducing motion blur. Something else is needed.

There are two main methods. The first is frame interpolation, where the TV itself creates brand-new frames that are sort of hybrids of the frame that came before, and the one that comes after. This can fool your brain enough that it doesn't blur the image. Depending how aggressive the interpolation is, however, it can lead to the soap opera effect, which makes movies look like ultra-smooth reality TV shows. Some viewers like the effect, but it's generally hated by film buffs and others who pay close attention to image quality.

There are different levels of this processing, where a little might reduce motion blur some, and not cause undue harm to the quality of the image. Or on the other end of the "dial," it's cranked up so that there's even less motion blur, but the movement is hyper-realistic and for many, distractingly unreal. Some TVs let you choose how much of this processing gets applied to the image, others have just a single setting. More on these settings further down.

The other alternative is black frame insertion (BFI) or a scanning backlight. This is where all or part of the backlight of the TV turns off (goes black). This effectively means the image doesn't "hold" in place, so your brain doesn't blur it. Do it poorly, however, and many people will see the image flicker. The light output of the TV also drops, as it's not outputting any light for a period of time.

Both of these techniques are what manufacturers use to come up with their "effective refresh rate" numbers. For example, a TV with a 60Hz refresh and a scanning backlight might claim to have an effective refresh rate of 120. A TV with a more elaborate BFI mode, and frame interpolation, might have a claimed effective refresh rate of "540." There's no transparency in how companies determine their "effective rate" numbers, but there is at least more consistency than there used to be.

It's also possible these features, when enabled, are bothersome over time. Some people are especially sensitive to a flickering backlight, so you might need to turn these features off. If you're concerned about that, or notice motion blur, it's best to find a TV that actually has a 120Hz refresh rate.

There are two things at play here. The first is simple, and one we've said many times before: don't trust marketing. At least, don't trust it at face value. Marketing is designed to sell you a product, not give you information about a product. That's secondary.

The second is being able to reduce motion blur. When 120Hz 1080p TVs first hit the market, they offered a noticeable improvement in motion resolution. The technology has only gotten better.

But if you're sensitive to motion blur, or you want to get the most from your Xbox Series X or PlayStation 5, it is worth checking for a true 120Hz TV. It would be a shame to let all that extra 4K resolution go to waste due to blur. It's also worth checking reviews for measurements and subjective takes on how the TV handles motion -- that's more useful than any manufacturer-supplied spec.

Note: This article was originally published in 2015 but has been updated regularly since.