Aspect Ratio Calculator for Images
Free online aspect ratio calculator. Calculate aspect ratio from image dimensions, find missing width or height, and get perfect crop suggestions for any aspect ratio.
Calculate 4:3 aspect ratio, 16:9, 1:1, and any custom ratio. Perfect for designers, photographers, and developers.
Calculate Aspect Ratio
Quick Presets
How to Use This Calculator
- 1Enter dimensions: Type your image width and height in pixels
- 2View aspect ratio: See the calculated ratio automatically
- 3Lock ratio (optional): Click the lock icon to maintain proportions when changing dimensions
- 4Use presets: Click any preset button to apply common aspect ratios
- 5Crop your image: Click "Crop Image" to apply the calculated dimensions
What is Aspect Ratio?
Aspect ratio is the proportional relationship between an image's width and height. It's expressed as two numbers separated by a colon (e.g., 16:9, 4:3). Understanding how to calculate aspect ratio is essential for:
Image Resizing
Maintain proportions when scaling images up or down
Cropping Images
Crop to specific ratios for social media or print
Display Optimization
Ensure images fit perfectly on screens and devices
Design Consistency
Maintain uniform proportions across multiple images
Common Aspect Ratios
16:9
Widescreen standard for HD video and modern displays
• YouTube videos
• HD TVs and monitors
• Laptop screens
• Example: 1920×1080
4:3
Traditional TV and computer monitor ratio
• Standard definition TV
• iPad screens
• Presentations
• Example: 1024×768
1:1
Square format for social media posts
• Instagram posts
• Profile pictures
• Square prints
• Example: 1080×1080
3:2
Classic photography and 35mm film ratio
• DSLR cameras
• Print photos (4×6)
• Professional photography
• Example: 3000×2000
9:16
Vertical format for mobile content
• Instagram Stories
• TikTok videos
• Snapchat
• Example: 1080×1920
21:9
Ultra-wide cinematic format
• Cinema movies
• Ultra-wide monitors
• Panoramic photos
• Example: 2560×1080
How to Calculate Aspect Ratio
Method 1: From Dimensions
Step 1: Take your image width and height (e.g., 1920×1080)
Step 2: Find the greatest common divisor (GCD)
Step 3: Divide both numbers by the GCD
Example:
1920 ÷ 120 = 16
1080 ÷ 120 = 9
Result: 16:9
Method 2: Calculate Missing Dimension
Formula: New Height = (Original Height × New Width) ÷ Original Width
Example:
Original: 1920×1080
New Width: 800
New Height = (1080 × 800) ÷ 1920
Result: 800×450
When to Use This Calculator
📱 Social Media Content
Calculate perfect dimensions for Instagram (1:1, 4:5, 9:16), Facebook (16:9), Twitter (16:9), and TikTok (9:16). Ensure your images look perfect on every platform.
🎨 Graphic Design
Maintain consistent proportions across design projects. Calculate dimensions for banners, posters, flyers, and digital artwork while preserving aspect ratios.
📸 Photography
Determine crop dimensions for prints (4×6, 5×7, 8×10). Calculate aspect ratios for different camera formats and ensure photos fit frames perfectly.
💻 Web Development
Calculate responsive image dimensions for websites. Ensure images scale properly across devices while maintaining aspect ratios and preventing distortion.
🎬 Video Production
Calculate dimensions for different video formats: 16:9 for YouTube, 1:1 for Instagram feed, 9:16 for Stories and Reels. Perfect for content creators.
🖨️ Print Design
Calculate dimensions for print materials: business cards, brochures, posters. Ensure designs maintain proper proportions when scaled for printing.
Frequently Asked Questions
How do I calculate aspect ratio from image dimensions?
To calculate aspect ratio, divide both width and height by their greatest common divisor (GCD). For example, 1920×1080 becomes 16:9 after dividing by 120. Our calculator does this automatically.
What is a 4:3 aspect ratio calculator used for?
A 4:3 aspect ratio calculator helps you find dimensions for traditional TV format, iPad screens, and presentations. Common 4:3 sizes include 1024×768, 800×600, and 1600×1200 pixels.
How do I find missing width or height?
Enter your known dimension and desired aspect ratio. The calculator automatically computes the missing dimension while maintaining the correct proportions. Perfect for resizing images.
What aspect ratio should I use for Instagram?
Instagram supports multiple ratios: 1:1 (square) for feed posts, 4:5 (portrait) for maximum visibility, and 9:16 (vertical) for Stories and Reels. Use our calculator to find exact dimensions.
Can I crop my image to a specific aspect ratio?
Yes! After calculating your desired dimensions, click the "Crop Image" button to use our crop tool. Upload your image and crop it to the exact aspect ratio you calculated.
What's the difference between 16:9 and 4:3?
16:9 is widescreen (modern TVs, YouTube), while 4:3 is traditional format (old TVs, iPads). 16:9 is wider and better for video content, while 4:3 is more square-shaped.
How do I maintain aspect ratio when resizing?
Lock the aspect ratio in our calculator, then enter either width or height. The calculator automatically calculates the other dimension to maintain perfect proportions without distortion.
What aspect ratio is best for printing photos?
Common print ratios: 3:2 (4×6 prints), 4:5 (8×10 prints), 5:7 (5×7 prints). Use our calculator to determine if your image needs cropping before printing to avoid cutting off important parts.
Pro Tips for Aspect Ratios
Always Maintain Ratio
Never stretch images - always maintain aspect ratio to prevent distortion and maintain quality.
Plan Before Shooting
Know your target aspect ratio before taking photos to minimize cropping and maximize composition.
Use Common Ratios
Stick to standard ratios (16:9, 4:3, 1:1) for better compatibility across platforms and devices.
Test on Devices
Preview your images on different devices to ensure they look good at your chosen aspect ratio.
Calculate Your Aspect Ratio Now
Free aspect ratio calculator for images. Calculate dimensions, find missing values, and get crop suggestions instantly.
Start Calculating