3840x2160 resolution
3840 × 2160
4K UHD (2160p) · 16:9 · 8,294,400 pixels · 8.29 megapixels · Broadcast and TV
What 3840x2160 is
Exactly four 1080p frames in a two-by-two grid, which is why 1080p content upscales to it without interpolation artefacts at integer scaling. It is the consumer 4K, distinct from the cinema one.
The numbers
| Width | 3,840 px |
| Height | 2,160 px |
| Aspect ratio | 16:9 |
| Total pixels | 8,294,400 |
| Megapixels | 8.29 MP |
| Compared with 1080p | 4.00× the pixels |
| Compared with 4K UHD | this is 4K UHD |
What 3840x2160 costs to move and to store
A frame is width × height × three bytes of colour, before any compression touches it. At 3840 × 2160 that is 24.88 MB per frame, and video is frames per second:
| Frame rate | Uncompressed | An hour of it |
|---|---|---|
| 24 fps | 597 MB/s | 2.15 TB |
| 30 fps | 746 MB/s | 2.69 TB |
| 60 fps | 1.49 GB/s | 5.37 TB |
| 120 fps | 2.99 GB/s | 10.75 TB |
Nobody ships that. It is the number codecs exist to get away from — a streamed 3840x2160 feed runs at a few tens of megabits, which is a compression ratio of several hundred to one, and it is why a still frame from a stream looks worse than a photograph of the same scene.
How close you have to sit for 3840x2160 to be worth it
The eye resolves about one arcminute of detail. Past a certain distance the pixels merge whatever the panel does, and a higher resolution stops being visible rather than stopping being better. That distance is the pixel pitch divided by the tangent of one arcminute:
| Screen | Pixels merge beyond |
|---|---|
| 13.3 in monitor or laptop | 0.26 m (0.9 ft) |
| 15.6 in monitor or laptop | 0.31 m (1 ft) |
| 24 in monitor or laptop | 0.48 m (1.6 ft) |
| 27 in monitor or laptop | 0.54 m (1.8 ft) |
| 32 in monitor or laptop | 0.63 m (2.1 ft) |
| 43 in television | 0.85 m (2.8 ft) |
| 55 in television | 1.09 m (3.6 ft) |
| 65 in television | 1.29 m (4.2 ft) |
| 75 in television | 1.49 m (4.9 ft) |
Sitting further back than the figure for your screen, 3840x2160 and the next resolution down look the same. That is the whole argument about 4K televisions in ordinary living rooms: the resolution is real and the seating position usually is not close enough to show it.
Pixel density at common screen sizes
A resolution on its own says nothing about sharpness — the same 3840x2160 panel is dense on a laptop and coarse on a television. Density is the diagonal in pixels divided by the diagonal in inches.
| Diagonal | Pixel density | |
|---|---|---|
| 13.3 in | 331 PPI | High density — the OS will scale the interface |
| 15.6 in | 282 PPI | High density — the OS will scale the interface |
| 24 in | 184 PPI | Sharp |
| 27 in | 163 PPI | Sharp |
| 32 in | 138 PPI | Comfortable at native size |
Other broadcast and tv resolutions
| Resolution | Name | Ratio | Megapixels |
|---|---|---|---|
| 1280×720 | HD (720p) | 16:9 | 0.92 MP |
| 1920×1080 | Full HD (1080p) | 16:9 | 2.07 MP |
| 7680×4320 | 8K UHD | 16:9 | 33.18 MP |
Closest in total pixels
- 4096×2160 — DCI 4K
- 5120×1440 — DQHD
- 3840×1600 — UWQHD+
- 3024×1964 — Laptop 14-inch HiDPI
- 3200×1800 — QHD+
- 2732×2048 — Tablet 12.9-inch
- 2880×1800 — Retina 15-inch
- 3440×1440 — UWQHD
Frequently asked questions
What is the aspect ratio of 3840x2160?
16:9.
How many pixels is 3840x2160?
8,294,400 pixels, or 8.29 megapixels.
Is 3840x2160 higher resolution than 1080p?
3840x2160 has 4.00× as many pixels as a 1920×1080 frame.
What size screen suits 3840x2160?
Pixel density is what decides that. 331 PPI at 13.3 in, 282 PPI at 15.6 in, 184 PPI at 24 in, 163 PPI at 27 in, 138 PPI at 32 in. Below roughly 110 PPI text starts to look coarse; above about 200 the operating system will usually scale the interface rather than render it at native size.