Aspect Ratio Calculator (Image & Video)
Find missing dimensions when resizing images, videos, screens, and canvases without distortion. Calculate simplified aspect ratios and scale pixels accurately.
How to Use Aspect Ratio Calculator (Image & Video)
Enter Current Dimensions
Input original width and height in pixels (e.g. 1920 x 1080).
Select or Lock Ratio
View the simplified ratio (16:9) or pick a preset (4:3, 1:1, 9:16).
Calculate Scaled Dimension
Enter a new width to compute matching height, or new height to compute width.
About Aspect Ratio Calculator (Image & Video)
Applies the Euclidean algorithm to find GCD(width, height) to reduce dimensions to simplest fractional form (w/GCD : h/GCD), then applies cross-multiplication for missing values.
Supported Formats
Operational Limits
- •Operates on positive integer and decimal dimensions.
Key Features
- Calculates exact simplified ratio using Greatest Common Divisor (GCD)
- Find missing width given height and ratio
- Find missing height given width and ratio
- Presets for 16:9 (HD/4K), 4:3 (Classic), 1:1 (Square), 9:16 (Reels/TikTok), 21:9 (Ultrawide)
- Visual scaling preview box
Frequently Asked Questions
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