Aspect Ratio Calculator
Find the simplified aspect ratio and decimal proportion for any screen resolution or image dimension. Solve for missing width or height.
Calculate Aspect Ratio
Simplified via Greatest Common DivisorHow Aspect Ratio is Calculated
The aspect ratio represents the lowest whole-number fraction of a display's width to height. The formula relies on finding the Greatest Common Divisor (GCD):
Worked Example: 2560 × 1440 (QHD)
To reduce 2560 × 1440:
Standard Aspect Ratios Comparison
| Aspect Ratio | Decimal | Common Uses & Resolutions |
|---|---|---|
| 16:9 | 1.78 : 1 | 1080p (1920×1080), 1440p (2560×1440), 4K (3840×2160), TVs |
| 16:10 | 1.60 : 1 | MacBook Air/Pro, Dell XPS, productivity laptops (2560×1600) |
| 21:9 | 2.33 : 1 | Ultrawide monitors (2560×1080, 3440×1440, 5120×2160), Cinema |
| 32:9 | 3.56 : 1 | Super Ultrawide gaming monitors (5120×1440 dual QHD) |
| 4:3 | 1.33 : 1 | iPad displays, retro CRT gaming, photography |
| 3:2 | 1.50 : 1 | Microsoft Surface devices, 35mm DSLR photography |
| 9:16 | 0.56 : 1 | Vertical smartphone video (TikTok, Reels, Shorts) |
Frequently Asked Questions
What is an aspect ratio?
An aspect ratio is the proportional relationship between the width and height of an image, video, or display screen. It is written as two numbers separated by a colon, such as 16:9 (width : height).
How do you calculate an aspect ratio?
To calculate aspect ratio, divide both the width and height by their Greatest Common Divisor (GCD). For 1920 × 1080, the GCD is 120: (1920 ÷ 120) : (1080 ÷ 120) = 16:9.
What is the most common screen aspect ratio?
16:9 is the universal standard for modern PC monitors, televisions, laptops, YouTube videos, and streaming services (1080p, 1440p, 4K UHD).
What is the difference between 16:9 and 16:10?
16:10 displays offer approximately 11% more vertical screen real estate than 16:9 displays. This makes 16:10 popular for productivity, coding, and MacBooks (2560×1600, 3024×1964) because more lines of text and code fit on screen.
What aspect ratio is used for Instagram and TikTok?
TikTok, Instagram Reels, and YouTube Shorts use 9:16 (vertical/portrait video, 1080×1920). Instagram feed posts traditionally support 1:1 (square, 1080×1080) and 4:5 (portrait, 1080×1350).