Find a ratio or calculate a missing dimension.
Calculated instantly in your browser.
| Ratio | Typical use | Common sizes |
|---|---|---|
| 16:9 | YouTube, TV, monitors | 1280×720, 1920×1080, 2560×1440, 3840×2160 |
| 9:16 | TikTok, Reels, Shorts, Stories | 720×1280, 1080×1920, 2160×3840 |
| 1:1 | Instagram and Facebook posts | 1080×1080, 1200×1200, 2048×2048 |
| 4:5 | Instagram portrait posts | 1080×1350, 1440×1800 |
| 4:3 | Presentations, older TV, iPad | 1024×768, 1440×1080, 2048×1536 |
| 3:2 | DSLR photos, prints | 1080×720, 3000×2000, 6000×4000 |
| 21:9 | Ultrawide monitors | 2560×1080, 3440×1440, 5120×2160 |
| 2.39:1 | Cinema widescreen | 1920×803, 3840×1607 |
Type a width and height, for example 1920 × 1080, to see its simplified ratio.
Pick a preset like 9:16 or type a custom ratio, then enter one side.
The missing side is calculated instantly and rounded to an even number for video encoders.
The calculator divides width and height by their greatest common divisor, then names the nearest standard ratio when there is one.
Know you need 9:16 at 1080 px wide? It returns 1920 px high instantly.
Most video codecs require even dimensions, so results can be rounded to the nearest even pixel.
A live frame shows the shape of the ratio so you can compare formats at a glance.
YouTube, TVs, monitors and most cameras: 1280×720, 1920×1080, 3840×2160.
TikTok, Instagram Reels, YouTube Shorts and Stories: 1080×1920.
Instagram and Facebook feed posts: 1080×1080 and 1080×1350.
Ultrawide monitors and cinematic widescreen: 2560×1080, 3840×1607.
Create new footage, plan your story or improve your source.
Divide the width and height by their greatest common divisor. 1920 × 1080 divided by 120 gives 16:9. The calculator does this for you.
9:16, the vertical format used by TikTok, Reels and Shorts.
4:5 (1080 × 1350) takes the most space in the feed, 9:16 is for Reels and Stories, and 1:1 is the classic square.
H.264 and most other encoders store color at half resolution, which requires even widths and heights.
No. The calculator is plain JavaScript that runs in your browser.
