Aspect Ratio Calculator
What is Aspect Ratio Calculator
An aspect ratio calculator works out the proportional relationship between width and height. Enter two dimensions to get the simplified ratio, such as 1920 by 1080 reducing to 16:9, or lock a ratio and fill in one side to find the other while the proportions stay intact.
How to use
- Pick Ratio mode to turn a width and height into a simplified ratio like 16:9.
- Pick Resize mode to scale a size while keeping its proportions.
- Type your original width and height in Resize mode.
- Enter the new width or the new height, and the matching side is filled in for you.
- Copy the result or share the link with your values already in place.
When to use it
Need to resize a 1920 by 1080 image to fit a 1280-pixel-wide slot without stretching it? Enter the original size, type 1280 as the new width, and the height fills in as 720 so the picture keeps its 16:9 shape. Handy for video exports, thumbnails, ad banners, and any layout where squashed images look wrong.
Frequently asked questions
What is an aspect ratio?
An aspect ratio describes the proportional relationship between width and height, written as two numbers like 16:9 or 4:3. A 1920 by 1080 image has a 16:9 ratio because both dimensions divide down to 16 and 9.
How do I resize an image without distortion?
Use Resize mode. Enter the original width and height, then type either the new width or the new height. The tool fills in the other side so the proportions stay the same and nothing gets stretched.
What are common aspect ratios?
16:9 is standard for video and most screens, 4:3 covers older displays and photos, 1:1 is the square used on social media, 3:2 is common on cameras, and 21:9 is for ultrawide monitors.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button, and anyone who opens the link will see your exact inputs ready to go.
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