Aspect Ratio Calculator
Calculate and convert aspect ratios between different resolutions.
Enter dimensions
×
Simplified Ratio
16:9
Decimal Ratio
1.7778
Closest standard
16:9
HD video, YouTube, most monitors
Proportional preview
16:9
Common aspect ratios
| Ratio | Decimal | Common use | |
|---|---|---|---|
| 16:9 | 1.778 | HD video, YouTube, most monitors | |
| 4:3 | 1.333 | Legacy TV, standard iPad | |
| 1:1 | 1.000 | Instagram posts, profile photos | |
| 9:16 | 0.563 | TikTok, Instagram Reels, vertical video | |
| 21:9 | 2.333 | Ultrawide monitors, cinematic | |
| 3:2 | 1.500 | DSLR cameras, Surface laptops | |
| 2:1 | 2.000 | Univisium, some smartphones | |
| 4:5 | 0.800 | Instagram portrait posts | |
| 5:4 | 1.250 | Old CRT monitors, 1280×1024 | |
| 2.39:1 | 2.390 | Anamorphic widescreen (cinema) | |
| 1.85:1 | 1.850 | Standard widescreen (cinema) | |
| 16:10 | 1.600 | Wuxga laptops, MacBook Air |
Find the simplified aspect ratio from any width and height, or calculate missing dimensions from a given ratio. Supports all common video, photo and screen ratios.
Key Features
Find Ratio Mode
Enter any width × height and get the exact simplified ratio, decimal value and closest standard ratio.
Scale Dimensions Mode
Enter a ratio (e.g. 16:9) and one dimension to instantly calculate the other — perfect for resizing.
Proportional Preview
A visual box scaled to the actual proportions gives an instant feel for the shape.
Common Ratios Table
11 common aspect ratios with decimal equivalents and real-world use cases. Click "Use →" to load any into the scale tool.
How to Use
- 1Choose "Find ratio" to get the ratio from dimensions, or "Scale dimensions" to compute a dimension from a ratio.
- 2In Find mode, enter width and height — the simplified ratio and closest standard appear instantly.
- 3In Scale mode, enter the ratio and lock either width or height, then type one value.