4K refers to super-sharp display and video technology where the resolution is roughly 4,000 pixels wide. Detail is the whole point of 4K – most of the time, you won’t be able to see the pixels in a 4K display, so everything looks natural and sharp. It’s great for photos, videos and gaming for this reason, but actually it’s superior for just about everything – it’s nicer when text looks smoother on a computer, for example.
The vast majority of the time, 4K refers to a specific resolution of 3840 x 2160 (which is also known as ‘Ultra HD’) – this is the resolution of all 4K TVs and 4K video streams from the likes of Netflix or YouTube. Some cameras record in what’s often known as ‘Cinema 4K’, which is a resolution of 4096 x 2160. You may find that some computer monitors refer to themselves as 4K, and will have a horizontal resolution around 4,000 pixels, but have a different height to the resolutions mentioned above, such as ultra-wide monitors. The width is what makes something 4K or not.
You’ll mostly see 4K referred to in TVs of 40 inches and above, in computer and laptop monitors, on video streaming services, and in video recording on cameras or phones.
Latest about 4K
The LG G6 OLED TV details leak, teasing more brightness and other upgrades
Leaked materials show LG's "Brightness Booster Ultra" and what may be the W6 Wallpaper TV
Here's what I want to see from every major TV brand in 2026
Every TV brand had a great year in 2025, but there's always room for improvement. So, I put together a wishlist for 2026.
The best TVs I tested in 2025, including LG, Samsung and TCL
I tested a lot of TVs in 2025, and these were the very best of the bunch.
Hisense unveils a 300-inch 4K laser projector, plus a new UST projector
Hisense unveils two new 4K laser projectors for images from 65 to 300 inches, including the PX4-Pro UST projector
Forget burn-in — a long-term test says OLED TVs are the most reliable buy
A new study confirms that burn-in isn't the TV bogeyman some people have been led to believe
LG announces next-gen version of its best OLED TV tech, and a new name
LG sets the stage for the next G-series OLED TV and multiple gaming monitors
6 new 4K Blu-rays from December 2025 to add to your collection
Just in time for the holidays, we take a look at new 4K discs we recommend adding to your 4K Blu-ray collection – or giving as gifts.
Want to know which 2025 LG OLED TV to buy? I tested three models side-by-side, and there's one clear winner
I evaluated the G5, C5 and B5 side-by-side to find out which is the best overall value.
