aspect-ratio-data

Common aspect ratios and screen, video and cinema resolutions as CSV and JSON, plus a small dependency-free JavaScript module to simplify a ratio, resize while keeping it, find the nearest standard ratio and work out letterbox or pillarbox bars.

• data/aspect-ratios.csv / .json: 25 ratios
• data/resolutions.csv / .json: 30 resolutions
• aspect-ratio.js: simplify, toDecimal, resize, nearestStandard, fit

An interactive calculator built on the same ratios and resolutions is at pixelhandbook.com.

Data

Every named row links to the Wikipedia article its numbers and name were checked against on 2026-09-15. The simplified/ratio, decimal and megapixels columns are calculated by scripts/build.mjs, not typed by hand, and the tests recompute them.

Columns

aspect-ratios: ratio (as usually written), width, height, simplified (whole numbers), decimal (width ÷ height, 3 decimals), name, source

resolutions: group (video, cinema, display), name, width, height, ratio (simplified), decimal, megapixels, source, note

Aspect ratios

Ratio	Simplified	Decimal	Name
1:1	1:1	1	Square
1.19:1	119:100	1.19	Movietone
5:4	5:4	1.25
4:3	4:3	1.333
1.375:1	11:8	1.375	Academy ratio
1.43:1	143:100	1.43	IMAX (about 1.43:1)
3:2	3:2	1.5
16:10	8:5	1.6
5:3	5:3	1.667
16:9	16:9	1.778	Widescreen
1.85:1	37:20	1.85	Flat (DCI)
256:135	256:135	1.896	DCI full container (4096 × 2160, 2048 × 1080)
2:1	2:1	2	Univisium
2.2:1	11:5	2.2	70 mm film
21:9	7:3	2.333
2.35:1	47:20	2.35	Anamorphic, films of 1958–1970 (also used loosely for 2.39:1)
64:27	64:27	2.37	Ultrawide monitors sold as 21:9 (2560 × 1080, 3440 × 1440 is 43:18)
2.39:1	239:100	2.39	Scope (DCI)
2.4:1	12:5	2.4
2.55:1	51:20	2.55	CinemaScope (early)
2.76:1	69:25	2.76	Ultra Panavision 70
32:9	32:9	3.556	Super-ultrawide (marketing name), e.g. DQHD
9:16	9:16	0.563
4:5	4:5	0.8
2:3	2:3	0.667

Resolutions

Group	Name	Size	Ratio	Decimal	MP	Note
video	DV 525/60 frame	720 × 480	3:2	1.5	0.35	Same frame size is used for 4:3 and 16:9 video, with different pixel aspect ratios
video	DV 625/50 frame	720 × 576	5:4	1.25	0.41	Same frame size is used for 4:3 and 16:9 video, with different pixel aspect ratios
video	720p	1280 × 720	16:9	1.778	0.92
video	1080p (Full HD)	1920 × 1080	16:9	1.778	2.07
video	1440p (QHD)	2560 × 1440	16:9	1.778	3.69
video	4K UHD	3840 × 2160	16:9	1.778	8.29
video	8K UHD	7680 × 4320	16:9	1.778	33.18
cinema	DCI 2K	2048 × 1080	256:135	1.896	2.21
cinema	DCI 2K Flat (1.85:1)	1998 × 1080	37:20	1.85	2.16
cinema	DCI 2K Scope (2.39:1)	2048 × 858	1024:429	2.387	1.76	Exact ratio 1024:429 (2.387:1)
cinema	DCI 4K	4096 × 2160	256:135	1.896	8.85
cinema	DCI 4K Flat (1.85:1)	3996 × 2160	37:20	1.85	8.63
cinema	DCI 4K Scope (2.39:1)	4096 × 1716	1024:429	2.387	7.03	Exact ratio 1024:429 (2.387:1)
display	VGA	640 × 480	4:3	1.333	0.31
display	SVGA	800 × 600	4:3	1.333	0.48
display	XGA	1024 × 768	4:3	1.333	0.79
display	WXGA	1280 × 800	8:5	1.6	1.02
display	SXGA	1280 × 1024	5:4	1.25	1.31
display	WXGA (16:9 variant)	1366 × 768	683:384	1.779	1.05	Close to 16:9, exactly 683:384
display	WXGA+	1440 × 900	8:5	1.6	1.3	Also called WSXGA
display	HD+	1600 × 900	16:9	1.778	1.44
display	WSXGA+	1680 × 1050	8:5	1.6	1.76
display	WUXGA	1920 × 1200	8:5	1.6	2.3
display	WQXGA	2560 × 1600	8:5	1.6	4.1
display	UWFHD	2560 × 1080	64:27	2.37	2.76	Sold as 21:9, exactly 64:27
display	UWQHD	3440 × 1440	43:18	2.389	4.95	Sold as 21:9, exactly 43:18
display	5K	5120 × 2880	16:9	1.778	14.75
display	UW5K	5120 × 2160	64:27	2.37	11.06	Sold as 21:9, exactly 64:27
display	DQHD	5120 × 1440	32:9	3.556	7.37	32:9
display	6K (Apple Pro Display XDR)	6016 × 3384	16:9	1.778	20.36

Things worth knowing from the table:

• Monitors sold as "21:9" are not 21:9. 2560 × 1080 and 5120 × 2160 are 64:27 (2.370:1) and 3440 × 1440 is 43:18 (2.389:1); 21:9 is 2.333:1.
• DCI "Scope" at 2048 × 858 and 4096 × 1716 is exactly 1024:429 (2.387:1), presented as 2.39:1.
• DV stores 720 × 480 and 720 × 576 frames for both 4:3 and 16:9 video, using different pixel aspect ratios. The ratios in this table are of the stored pixels.

JavaScript

Works in Node.js 20.10+ (import ... with { type: 'json' }) and in browsers that support JSON import attributes (tested in Chromium 153).

import { simplify, resize, nearestStandard, fit } from './aspect-ratio.js';

simplify(2560, 1080);                       // [64, 27]
resize(1920, 1080, { width: 1000 });        // { width: 1000, height: 563, ratioChangePercent: -0.088... }
resize(1920, 1080, { width: 1000 }, 'even'); // height 562 (even sizes for 4:2:0 video)
nearestStandard(2048, 858);                 // { ratio: '2.39:1', name: 'Scope (DCI)', differencePercent: -0.127... }
fit(2048, 858, 1920, 1080);                 // { mode: 'letterbox', width: 1920, height: 804, bar: 138, usedPercent: 74.479... }

• simplify(width, height) accepts decimals up to 6 places (2.39, 1 → 239:100).
• resize rounds the calculated side to whole numbers by default; 'even' rounds to even numbers and 'none' keeps decimals. ratioChangePercent shows how much rounding moved the ratio.
• nearestStandard compares against data/aspect-ratios.json as landscape and turns the result back for portrait sizes.
• fit places content inside a screen without cropping. bar is the size of each bar; usedPercent is the share of the screen the picture covers.

Development

npm run build   # regenerate data/ from scripts/data-source.mjs
npm test        # node --test

License

MIT