Aspect Ratio Calculator
Calculate the aspect ratio of any resolution, or find the missing dimension. Supports 16:9, 4:3, 1:1, 9:16 and all common screen formats with a live visual preview.
Common Screen Resolutions
| Name | Dimensions | Ratio |
|---|---|---|
| 4K UHD | 3840×2160 | 16:9 |
| Full HD 1080p | 1920×1080 | 16:9 |
| HD 720p | 1280×720 | 16:9 |
| Instagram Square | 1080×1080 | 1:1 |
| Instagram Portrait | 1080×1350 | 4:5 |
| Reels / Shorts | 1080×1920 | 9:16 |
| Twitter / X | 1200×675 | 16:9 |
| DSLR Photo | 6000×4000 | 3:2 |
| Ultrawide | 2560×1080 | 64:27 |
| Classic TV / iPad | 800×600 | 4:3 |
Frequently Asked Questions
An aspect ratio expresses the proportional relationship between a frame's width and its height, written as W:H (e.g. 16:9). It determines how content looks on different screens. A 16:9 video plays perfectly on a widescreen TV but shows black bars on a 4:3 monitor. Choosing the wrong ratio for a platform (e.g. uploading a 16:9 clip to Instagram Reels which expects 9:16) causes letterboxing or cropping, hurting engagement.
YouTube standard videos: 16:9 (1920×1080 or 1280×720). YouTube Shorts: 9:16 (1080×1920). Instagram feed square: 1:1 (1080×1080). Instagram portrait (best organic reach): 4:5 (1080×1350). Instagram Reels / TikTok / Facebook Reels: 9:16 (1080×1920). Twitter/X image card: 16:9 (1200×675). LinkedIn article cover: 1.91:1 (1200×627).
Divide the width by 16 and multiply by 9. For example, a 1280 px wide video has a height of 1280 ÷ 16 × 9 = 720 px. In general: Height = Width × (Ratio H ÷ Ratio W). Use the "Find Dimension" mode in this calculator to get the result instantly without manual arithmetic.
16:9 (decimal 1.778) is the standard for consumer televisions, streaming platforms, and most smartphones in landscape. 16:10 (also written 8:5, decimal 1.600) is common on MacBooks and business laptops because the extra vertical space helps productivity. The visible difference is subtle, but content mastered for 16:9 will have small black bars on a 16:10 screen and vice versa.