Aspect Ratio Calculator
Calculate and scale aspect ratios
Aspect Ratio Calculator
Common Aspect Ratios
Scale Dimensions
Maintain aspect ratio while scaling
How to Use
- Enter width and height to calculate aspect ratio
- Use presets for common ratios like 16:9, 4:3, etc.
- Scale dimensions while maintaining aspect ratio
- Enter new width or height to auto-calculate the other dimension
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About Aspect Ratio Calculator
Calculate and maintain aspect ratios for images, videos, and screens with our aspect ratio calculator. Aspect ratio is the proportional relationship between width and height, critical for responsive design, video production, image resizing, and maintaining visual quality. Whether you need to resize images without distortion, crop videos to different formats, design responsive layouts, or scale graphics proportionally, this tool ensures perfect aspect ratio maintenance. Input original dimensions and desired width or height - the calculator instantly provides the corresponding dimension to maintain ratio. Essential for web designers creating responsive images, video editors working with different formats (16:9, 4:3, 21:9), graphic designers scaling artwork, photographers cropping photos, and developers implementing responsive design. Supports common ratios like 16:9 (widescreen), 4:3 (standard), 1:1 (square), and custom ratios for any creative project.
Key Features
Maintain Aspect Ratio
Calculate missing dimension to maintain perfect proportions. No distortion or stretching - images and videos scale correctly.
Common Ratio Presets
Quick-select popular aspect ratios: 16:9 (HD video), 4:3 (standard), 1:1 (Instagram square), 21:9 (ultrawide), 9:16 (vertical video).
Ratio Simplification
Simplifies ratios to lowest terms. 1920×1080 simplifies to 16:9. Understand the fundamental ratio of any dimensions.
Dimension Scaling
Scale images up or down while maintaining proportions. Input target width or height, get the corresponding dimension automatically.
Format Conversion
Calculate crop dimensions to convert between aspect ratios. Determine exact pixels to crop when changing from 4:3 to 16:9, for example.
Responsive Design Helper
Plan responsive breakpoints and image sizes. Ensure images scale proportionally across all device sizes.
How to Use Aspect Ratio Calculator
Enter Original Dimensions
Enter the original width and height of your image or video in pixels. These are the current dimensions you're working with.
View Aspect Ratio
The calculator automatically shows the aspect ratio (e.g., 16:9) of your input dimensions. This is the proportional relationship between width and height.
Enter New Dimension
To resize, enter your desired new width OR new height. Input only one dimension to maintain the aspect ratio.
Get Corresponding Dimension
The calculator provides the corresponding dimension to maintain the aspect ratio. This ensures your image or video won't be distorted.
Use Preset Ratios
Use preset ratios (16:9, 4:3, 1:1) for quick conversion to common formats. Perfect for standard video and image formats.
Calculate Crop Dimensions
For cropping, calculate the exact dimensions needed to achieve your target aspect ratio while preserving content.
Frequently Asked Questions
What does 16:9 aspect ratio mean?
16:9 means width is 16 units for every 9 units of height. Common in HD TVs, computer monitors, and YouTube videos. 1920×1080 (Full HD) and 3840×2160 (4K) are both 16:9. This widescreen format is the standard for modern video content.
How do I resize an image without distorting it?
Use our calculator to find the correct dimensions. If your image is 800×600 (4:3) and you want 400px width, the height must be 300px (400÷800×600=300) to avoid distortion. Never just set arbitrary width and height.
What aspect ratio should I use for Instagram?
Instagram feed posts work best at 1:1 (square, like 1080×1080) or 4:5 (portrait, like 1080×1350). Stories and Reels use 9:16 (vertical, like 1080×1920). Landscape posts support 1.91:1 (like 1080×566).
Can I change aspect ratio without cropping?
No, changing aspect ratio means either cropping (cutting parts off) or letterboxing (adding black bars). You can't change proportions without one of these. Cropping removes content; letterboxing adds empty space.
What's the difference between 4:3 and 16:9?
4:3 is the old TV standard (more square, like old TVs and computer monitors). 16:9 is modern widescreen (wider, like HDTV and most current screens). Converting between them requires either cropping sides (4:3 to 16:9) or top/bottom (16:9 to 4:3).
What aspect ratio is best for YouTube?
16:9 is YouTube's native ratio (like 1920×1080). Other ratios play but have letterboxing (black bars). For best viewer experience, upload 16:9. Vertical videos (9:16) now work for Shorts.
How do I crop to change aspect ratio?
Use our calculator to determine target dimensions. If converting 1600×1200 (4:3) to 16:9, calculate: 1600×9÷16=900. Crop to 1600×900, removing 150px from top/bottom. Or keep height: 1200×16÷9=2133, crop to 1600×1200.
Does aspect ratio affect quality?
Aspect ratio itself doesn't affect quality - resolution does. However, changing ratios requires cropping (loses content) or stretching (distorts image). Always maintain original ratio and use high enough resolution for final dimensions.
Use Cases
- Responsive Web Design: Calculate image dimensions for different screen sizes. Ensure images display correctly on mobile, tablet, and desktop without distortion.
- Video Production and Editing: Convert videos between formats (16:9 to 9:16 for vertical), maintain quality when resizing, and crop to platform-specific requirements (YouTube, TikTok, Instagram).
- Social Media Content: Size images perfectly for each platform: Instagram (1:1, 4:5), Twitter (16:9), Pinterest (2:3). Avoid cropping important content with correct dimensions.
- Photography and Print: Crop photos to print sizes without distortion. Calculate dimensions for different print ratios while maintaining image composition.
- Graphic Design and Branding: Scale logos and graphics consistently across materials. Maintain brand integrity with properly proportioned assets for all use cases.