Aspect ratio calculator
Enter width and height to get the simplified aspect ratio.
Aspect ratio calculator
This aspect ratio calculator finds the proportion between width and height (for example 16:9) from pixel dimensions, plus the decimal value. Handy for video, screens, photos and design.
How it’s calculated
ratio = width : height (divided by their GCD)
Width and height are divided by their greatest common divisor to give the proportion in its simplest form. For example, 1920 × 1080: GCD = 120 → 1920/120 : 1080/120 = 16:9.
Common aspect ratios
- 16:9 — video and modern screens (Full HD, 4K).
- 4:3 — older monitors and photos.
- 1:1 — square (social media).
- 21:9 — ultrawide.
- 9:16 — vertical (mobile, stories).
Frequently asked questions
What is aspect ratio? The proportion between the width and height of an image or screen.
Does keeping the ratio affect quality? No: scaling while keeping the proportion avoids distorting the image.
Can it help me resize? Yes: knowing the ratio, fix one side and compute the other without distortion.