Aspect Ratio Calculator: The Filmmaker and Designer's Best Friend
Have you ever resized an image only to have it look squashed or stretched? Or uploaded a video to Instagram only to have the top of your head cropped off? These are aspect ratio problems.
Our Free Aspect Ratio Calculator solves this. It ensures that when you change the width of an image, the height updates proportionally to maintain the perfect shape. Whether you are dealing with 4K video, social media posts, or responsive CSS containers, this tool does the math for you.
Understanding Common Ratios
16:9 (Widescreen)
The global standard for television, computer monitors, and YouTube.
Common Sizes: 1920x1080 (1080p), 3840x2160 (4K).
9:16 (Vertical)
The standard for mobile consumption. If you are creating content for TikTok, Instagram Stories/Reels, or YouTube Shorts, you must design for this ratio.
Common Sizes: 1080x1920.
4:3 (Traditional)
The shape of old tube TVs (SD) and, interestingly, the iPad. It allows for a taller viewing area than 16:9, making it great for reading and browsing the web.
Common Sizes: 1024x768.
1:1 (Square)
Perfect squares. Originally popularized by Instagram, they are still very effective for social media feed posts as they occupy a large amount of vertical screen real estate on mobile.
Common Sizes: 1080x1080.
How to Use This Tool for Web Design
In modern CSS, we often use the `aspect-ratio` property.
.card-image {
width: 100%;
aspect-ratio: 16 / 9;
object-fit: cover;
}This code ensures that no matter how wide the card gets on a responsive screen, the image container will always remain a perfect 16:9 rectangle, preventing layout shifts (CLS) which harm SEO.
How to Use This Tool for Video Editing
If you are trying to fit cinematic footage (21:9) onto a standard screen (16:9), you have two choices:
- Letterboxing: Adding black bars to the top and bottom.
- Pan & Scan: Cropping the sides to fill the height.
Use this calculator to determine exactly how many pixels you need to crop or how wide your black bars needs to be.