Screen resolution history: VGA to 4K and 8K

Apr 27, 2026 5 min read

“1080p”, “4K”, “Retina” — display resolution names have piled up. This article walks through the lineage and the PPI math.

Common resolutions

Name	Pixels	Aspect	Typical use
VGA	640 × 480	4:3	1987, IBM PS/2
SVGA	800 × 600	4:3	early 1990s
XGA	1024 × 768	4:3	late 1990s
WXGA	1280 × 800	16:10	early laptops
HD (720p)	1280 × 720	16:9	HDTV
WSXGA+	1680 × 1050	16:10	high-end monitor
Full HD (1080p)	1920 × 1080	16:9	TVs, monitors
WUXGA	1920 × 1200	16:10	pro use
QHD (2K)	2560 × 1440	16:9	high-end monitor
4K UHD	3840 × 2160	16:9	4K TVs / monitors
5K	5120 × 2880	16:9	iMac 5K
8K UHD	7680 × 4320	16:9	next-gen TVs

VGA to HD: the timeline

1987 — VGA

IBM PS/2 introduced 640 × 480. State of the art at the time.

1990s — SVGA, XGA

Office computing standardized on 800 × 600, then 1024 × 768. CRT monitors dominated.

2000s — WXGA, SXGA

Laptops normalized at 1280 × 800. Desktops often used 1280 × 1024 (5:4).

Late 2000s onward — Full HD

LCD TVs standardized at 1920 × 1080. “Full HD” / “1080p”.

HD vs Full HD vs 4K

“HD” gets confusing:

HD Ready — 1280 × 720 (720p).
Full HD — 1920 × 1080 (1080p).
2K — 1920 × 1080 (cinema convention) or 2560 × 1440.
QHD — 2560 × 1440 (4× of HD).
WQHD — same as QHD.
4K UHD — 3840 × 2160 (consumer TV).
4K (DCI 4K) — 4096 × 2160 (cinema).

“2K” and “4K” mean different things in cinema vs consumer.

Phone resolutions

Device	Pixels	PPI
iPhone 4 (2010)	960 × 640	326
iPhone 6 (2014)	1334 × 750	326
iPhone 6 Plus	1920 × 1080	401
iPhone 14 Pro	2556 × 1179	460
iPhone 15 Pro Max	2796 × 1290	460
Galaxy S23 Ultra	3088 × 1440	500

Phones run high PPI; Retina-grade (≥ 300 PPI) is the floor.

PPI computation

PPI = √(width² + height²) / diagonal in inches

Example: 1920 × 1080 on a 24” monitor:

pixel diagonal = √(1920² + 1080²) = √(3,686,400 + 1,166,400) = 2202.9
PPI = 2202.9 / 24 = 91.8

24” Full HD ≈ 92 PPI — comfortable for typical viewing distance.

iPhone 14 Pro at 6.1” / 2556 × 1179:

pixel diagonal = √(2556² + 1179²) = √(6,533,136 + 1,389,841) = 2814.7
PPI = 2814.7 / 6.1 = 461.4

460+ PPI — Retina-grade.

What “Retina” means

Apple’s term for “you can’t see individual pixels at the typical viewing distance”:

iPhone — ≥ 300 PPI (~25 cm distance).
iPad — ≥ 260 PPI (~38 cm).
MacBook — ≥ 220 PPI (~50 cm).
iMac — ≥ 220 PPI (~75 cm).

Greater distance → lower PPI still qualifies.

Aspect ratios

Aspect	Resolutions
4:3	640×480, 1024×768
16:10	1280×800, 1920×1200, 2560×1600
16:9	1280×720, 1920×1080, 3840×2160
21:9	2560×1080, 3440×1440, 5120×2160
32:9	3840×1080, 5120×1440
18.5:9	2436×1125 (iPhone X)
19.5:9	2778×1284 (iPhone 12+)

Phones use unusual ratios for notches / dynamic islands.

DPI vs PPI

Often conflated:

PPI — pixels per inch on screen.
DPI — dots per inch in print.

Used interchangeably in many places.

Print conventions:

72 DPI — coarse (old monitor norm).
150 DPI — standard print.
300 DPI — high-quality print.
600 DPI+ — high-resolution printers.

CSS pixels vs device pixels

High-DPI gotcha:

CSS width: 100px.
iPhone Retina — 200 physical pixels (2x).
4K monitor — 100–200 physical pixels (depends on OS scaling).

window.devicePixelRatio reads the ratio:

console.log(window.devicePixelRatio);
// iPhone 14 Pro: 3
// 24" Full HD monitor: 1
// 4K at 150% scale: 1.5

Ultrawide monitors

21:9 (2560 × 1080, 3440 × 1440) or 32:9 (5120 × 1440):

Productivity — side-by-side windows.
Video editing — long timelines.
Gaming — wider FOV.
Caveat — old games and video letterbox.

Trades desk footprint for “wider field of view”.

State of 8K

7680 × 4320 — 4× the pixels of 4K UHD:

TVs exist but content is sparse.
8K streaming is limited.
At typical living-room distance, 4K vs 8K is hard to tell apart.
Adoption lags 4K significantly.

Used in professional contexts (medical imaging, digital signage).

Monitor sizing rules of thumb

By diagonal:

Size	Recommended	PPI
24”	Full HD	92
27”	QHD	109
32”	4K	137
34” ultrawide	3440 × 1440	110
38” ultrawide	3840 × 1600	110

“4K on 24” is overkill, Full HD on 32” looks coarse” is the heuristic.

Summary

VGA → HD → Full HD → 4K → 8K progression.
HD = 720p, Full HD = 1080p, 4K = 2160p.
PPI = √(w² + h²) / diagonal inches.
Phones run 300+ PPI (Retina-grade).
Aspect ratios diversified from 4:3 → 16:9 → 21:9.

For screen-size and PPI calculations, the screen resolution tool on this site computes both directions.