Aspect Ratio Calculator

Design

Calculate image and video aspect ratios (16:9, 4:3, 1:1, 21:9, 9:16) and compute proportional dimensions for responsive layouts.

Local Browser Execution: 100% Client-Side. No images are uploaded to any server.
Proportional Height = (Width × RatioHeight) / RatioWidth; GCD(W, H) for simplified ratio

Understanding Your Results

Calculates proportional geometric dimensions: (Target Width / Target Height) = (Ratio Width / Ratio Height). Visual preview displays the container shape.

Practical Guidance & Next Steps

Use 16:9 (1920x1080) for YouTube videos and desktop headers. Use 9:16 (1080x1920) for Instagram Reels, TikTok, and YouTube Shorts.

What is this?

A mathematical dimension calculator that maintains exact geometric proportions when resizing images, videos, UI mockups, and canvases.

How does it work?

1. Enter original Width and Height (or pick a standard preset like 16:9 Full HD 1920x1080). 2. Change target Width or Height. 3. The corresponding dimension calculates automatically to preserve the exact ratio.

Why use it?

Avoid distorted or stretched images, calculate video crop dimensions for Instagram Reels / TikTok (9:16) vs YouTube (16:9), and configure responsive CSS `aspect-ratio` properties.

Technical Scope & Calculation Limitations

Outputs rounded integer pixel coordinates suitable for web graphics and video rendering engines.

Frequently Asked Questions

16:9 is standard for YouTube and modern TVs; 9:16 is vertical video for TikTok, Reels, and Shorts; 4:3 is traditional TV; 1:1 is square for Instagram posts.
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