Frequently Asked Questions

Aspect ratio is the proportional relationship between a width and height, expressed as W:H. For example, 16:9 means for every 16 units of width there are 9 units of height. It stays constant regardless of actual pixel dimensions.

16:9 is the standard for HD/4K video and most monitors. 4:3 was the old TV standard. 21:9 is ultra-wide cinema. 9:16 is vertical video (TikTok/Instagram Stories). 1:1 is square (Instagram posts).

To maintain ratio: new height = new width × (original height / original width). Or: new width = new height × (original width / original height). This calculator does this for you — enter any two values and get the third.

Aspect Ratio Calculator — Overview

The Aspect Ratio Calculator helps you scale image and video dimensions while keeping the proportional relationship between width and height perfectly intact. Whether you are resizing a photograph for a website, preparing a video for a specific platform, cropping a design mockup, or calculating the display size of embedded media, maintaining the correct aspect ratio prevents unwanted stretching or squishing. Enter any two of the four values — original width, original height, new width, or new height — and the calculator solves for the missing dimension. It also simplifies the ratio to its canonical form (e.g., 1920×1080 becomes 16:9) so you can quickly identify the standard format you are working with. Common presets for 16:9, 4:3, 1:1, and other ratios are available for one-click selection.

Common Use Cases

Resizing images for web pages without distortion

Scaling video exports to match YouTube, Instagram, or TikTok specs

Calculating print dimensions from screen pixel measurements

Verifying that a cropped image still matches the original ratio

How to Use This Tool

Enter the original width and height of your image or video, then type in either the desired new width or new height. The tool automatically calculates the missing dimension to preserve the ratio. You can also enter any two dimensions to instantly identify the simplified aspect ratio.

Aspect Ratio Calculator

Frequently Asked Questions