Aspect Ratio Calculator

What Is an Aspect Ratio Calculator?

This free aspect ratio calculator helps you calculate width, height, and aspect ratios for images, videos, screens, and designs. Whether you need to scale an image while maintaining proportions, find the correct height for a 16:9 video at a specific width, convert portrait dimensions to landscape, or simply understand the ratio of any set of dimensions — this aspect ratio calculator gives you the answer instantly.

Aspect ratio is the proportional relationship between width and height. It is expressed as two numbers separated by a colon, such as 16:9 or 4:3. Maintaining the correct aspect ratio when resizing images or videos prevents distortion — a stretched or squashed image immediately looks unprofessional. This aspect ratio calculator prevents that by calculating exact scaled dimensions.

Common Aspect Ratios Explained

• 16:9 (Widescreen HD): The universal standard for HD and 4K televisions, YouTube videos, laptop screens, and most modern monitors. A 1920×1080 (Full HD) display is 16:9.
• 4:3 (Standard): The classic TV and computer monitor ratio from before widescreen became standard. Still used for some presentations, older photos, and certain social platforms.
• 1:1 (Square): Instagram’s original photo format. Used for profile pictures, thumbnails, and any content designed to appear equally wide and tall.
• 9:16 (Portrait): The vertical flip of 16:9. Used for Instagram Stories, TikTok, YouTube Shorts, and Snapchat — any full-screen mobile vertical content.
• 4:5 (Instagram Portrait): Instagram’s recommended portrait post ratio — slightly less tall than 9:16, showing more content in the feed without being cropped.
• 3:2 (DSLR Photo): The native aspect ratio of most digital SLR cameras, inherited from 35mm film. Standard for photography.
• 21:9 (Ultrawide): Used by ultrawide monitors and cinematic widescreen films. Provides an immersive field of view for gaming and video editing.

Aspect Ratio Calculator — Frequently Asked Questions