Aspect Ratio & Resolution Calculator
Free aspect ratio calculator. Find the ratio of any width and height (like 1920×1080 = 16:9), resize while keeping proportions, and see common ratios and resolutions.
CSS: aspect-ratio: 16 / 9;
Common aspect ratios and resolutions
| Ratio | Used for | Common resolutions |
|---|---|---|
| 16:9 | HD/4K TV, YouTube, monitors, laptops | 1280×720, 1920×1080, 2560×1440, 3840×2160 |
| 9:16 | TikTok, Instagram Reels and Stories, YouTube Shorts | 720×1280, 1080×1920 |
| 4:3 | Older TVs and monitors, iPad, many compact cameras | 640×480, 1024×768, 1600×1200, 2048×1536 |
| 3:2 | DSLR and mirrorless photos, 4×6 in prints, Surface laptops | 1080×720, 3000×2000, 6000×4000 |
| 1:1 | Instagram square posts, profile pictures, album art | 1080×1080, 2048×2048 |
| 4:5 | Instagram portrait feed posts | 1080×1350 |
| 16:10 | MacBooks and many laptop and office monitors | 1280×800, 1920×1200, 2560×1600 |
| 21:9 | Ultrawide monitors and cinematic video | 2560×1080, 3440×1440, 5120×2160 |
| 2:1 | Twitter/X in-feed images, panoramic banners | 1200×600, 2000×1000 |
| 1.91:1 | Open Graph link previews (Facebook, LinkedIn) | 1200×630 |
What is a Aspect Ratio & Resolution Calculator?
An aspect ratio calculator is a graphic and video utility that computes the proportional relationship between the width and height of an image, video, or digital display. By applying greatest common divisor (GCD) mathematics, it determines the simplified ratio (such as 16:9 widescreen, 4:3 standard, 1:1 square, or 21:9 ultrawide) and automatically calculates scaled dimensions to prevent visual distortion. Designers, video editors, and front-end developers use this calculator to size responsive banners, video assets, and UI viewports.
Execution Privacy:Toolbrix processes this utility using🔒 Processed locally — calculations run in your browser.
How to use this Aspect Ratio & Resolution Calculator
Enter the original width and height in pixels, or click a preset such as 16:9, 4:3 or 9:16.
Read the simplified ratio, its decimal value and the nearest common ratio.
Type a new width to get the matching height, or a new height to get the matching width.
Copy the CSS aspect-ratio line if you are sizing an element on a web page.
Frequently Asked Questions
Q:What is the aspect ratio of 1920×1080?
16:9. Divide both sides by their greatest common divisor, 120: 1920 ÷ 120 = 16 and 1080 ÷ 120 = 9.
Q:What is the aspect ratio of 1920×1280?
3:2, the same shape as most camera photos. 1920 ÷ 640 = 3 and 1280 ÷ 640 = 2.
Q:How do I calculate height from width for 16:9?
Height = width × 9 ÷ 16. For 1280 px wide: 1280 × 9 ÷ 16 = 720 px.
Q:How do I calculate a 4:3 size?
Height = width × 3 ÷ 4, or width = height × 4 ÷ 3. For example 1024 × 3 ÷ 4 = 768, so 1024×768 is 4:3.
Q:Why does 1366×768 show 683:384?
Some screen sizes are not exactly a standard ratio. 1366×768 simplifies to 683:384, which is 1.779:1, so the calculator also shows it is close to 16:9 (1.778:1).
Q:What aspect ratio should I use for Instagram and TikTok?
Use 9:16 (1080×1920) for Reels, Stories and TikTok, 4:5 (1080×1350) for portrait feed posts, and 1:1 (1080×1080) for square posts.
Related Tools
Explore similar micro-utilities and developer tools on Toolbrix.
Social Media Image Size Cheat Sheet & Reference
Dimensions & aspect ratios for X, Instagram, LinkedIn, YouTube, Facebook, and TikTok banners.
In-Browser Image Resizer & WEBP Compressor
Resize dimensions and compress JPG/PNG/WEBP files entirely in browser Canvas.
Screen Resolution & Viewport Tester
Inspect real-time browser window dimensions, screen resolution, device pixel ratio, and orientation.