How to Use AspectRatioChecker
This comprehensive guide will walk you through all the features of AspectRatioChecker, helping you make the most of this powerful yet simple tool for all your aspect ratio needs.
Quick Navigation
Using the Aspect Ratio Calculator
The core feature of AspectRatioChecker is the aspect ratio calculator, which helps you determine the exact ratio between width and height dimensions.
Enter Your Dimensions
On the Calculator tab, enter your width and height values in pixels in the respective input fields. For example, enter 1920 for width and 1080 for height to calculate the aspect ratio of a Full HD video.
Pro Tip
You can enter any unit of measurement (pixels, inches, centimeters, etc.) as long as both width and height use the same unit. The aspect ratio will be the same regardless of the unit.
View Your Results
After entering dimensions, the calculator instantly displays:
- Aspect Ratio: The simplified ratio in the format width:height (e.g., 16:9)
- Ratio Name: Common name for standard ratios (e.g., "Widescreen (16:9)")
- Decimal Ratio: The width divided by height (e.g., 1.778)
- Visual Representation: A proportional rectangle showing the shape of your aspect ratio
Pro Tip
The visual representation helps you intuitively understand the proportions. A warning will appear for extreme aspect ratios that might indicate a mistake in your input.
Use Common Ratio Presets
Below the calculator, you'll find buttons for common aspect ratios like 16:9, 4:3, 1:1, etc. Clicking any of these buttons will automatically update the width and height fields to values that match the selected ratio.
This is useful when you know the ratio you want but need to determine appropriate pixel dimensions.
Working with the Resize Calculator
The resize calculator helps you maintain aspect ratio when changing dimensions - essential for resizing images without distortion.
Start with Your Original Dimensions
First, enter your original width and height in the main calculator at the top of the page. This establishes the aspect ratio you want to maintain.
Calculate New Height from Width
In the "If width is:" section, enter your desired new width. Then click "Calculate Height" to determine the appropriate height that maintains the original aspect ratio.
Pro Tip
Use the rounding dropdown to control how the calculated height is rounded:
- None (exact): Shows the precise value, which may include decimals
- Nearest integer: Rounds to the closest whole number
- Round down/up: Always rounds down or up to the nearest whole number
- Even dimensions: Ensures both dimensions are even numbers (useful for video encoding)
Calculate New Width from Height
Alternatively, in the "If height is:" section, enter your desired new height and click "Calculate Width" to determine the appropriate width that maintains the original aspect ratio.
This is particularly useful when you have a specific height constraint, such as fitting an image into a fixed-height container on a website.
Uploading and Analyzing Images
The Upload Image feature allows you to analyze existing images to determine their aspect ratio and other properties.
Upload an Image
There are three ways to upload an image:
- Drag and drop: Simply drag an image file from your computer and drop it onto the upload area
- Click to browse: Click the upload area to open a file browser and select an image
- Paste from clipboard: Copy an image and press Ctrl+V (or Cmd+V on Mac) while on the page
Privacy Note
All image processing happens locally in your browser. Your images are never uploaded to any server or stored anywhere outside your device.
Import from URL
If your image is already online, you can analyze it by entering its URL in the "Import from URL" section and clicking "Load Image".
This works with direct image links (URLs that end with .jpg, .png, etc.) from most websites.
Note
Some websites prevent their images from being loaded on other sites (CORS restrictions). If you encounter an error, try downloading the image and uploading it directly instead.
View Image Analysis
After uploading, you'll see a preview of your image along with detailed information:
- Dimensions: The exact width and height in pixels
- Aspect Ratio: The simplified ratio (e.g., 16:9)
- Ratio Name: Common name if it matches a standard ratio
- Decimal Ratio: The width divided by height
- File Size: The size of the image file
- File Type: The image format (JPEG, PNG, etc.)
Understanding Crop Visualization
The crop visualization feature helps you understand how your image would need to be cropped to fit different aspect ratios - essential for preparing content for various platforms.
Upload an Image
First, upload an image using any of the methods described in the previous section.
Select a Target Aspect Ratio
In the Crop Visualization section below your uploaded image, use the dropdown menu to select the target aspect ratio you want to visualize. Options include:
- 16:9 (Widescreen)
- 4:3 (Standard)
- 1:1 (Square)
- 4:5 (Instagram Portrait)
- 9:16 (Mobile Portrait)
- 2.35:1 (Cinemascope)
Interpret the Crop Preview
The crop preview shows how your image would be cropped to fit the selected aspect ratio. The preview maintains the maximum possible area of your original image while conforming to the new ratio.
Below the preview, you'll see:
- Original: Your image's original dimensions
- Cropped: The dimensions after cropping to the new ratio
- Lost Area: The percentage of the original image that would be cropped out
Pro Tip
A high "Lost Area" percentage indicates that the target aspect ratio is significantly different from your original image. Consider shooting or creating content with the target ratio in mind to minimize cropping.
Using Platform-Specific Guides
The Platform Guides tab provides recommended aspect ratios for all major social media and content platforms, helping you prepare perfectly sized content.
Navigate to Platform Guides
Click the "Platform Guides" tab in the main navigation to access platform-specific recommendations.
Search for Specific Platforms or Content Types
Use the search box at the top of the Platform Guides section to quickly find information about specific platforms (e.g., "Instagram") or content types (e.g., "story" or "thumbnail").
The search filters the platform cards in real-time as you type.
View Platform-Specific Recommendations
Each platform card shows recommended aspect ratios for different content types on that platform. For example, the Instagram card includes ratios for feed posts, stories, reels, and profile pictures.
Apply a Preset to the Calculator
Click the "Apply" button on any ratio recommendation to automatically set those dimensions in the calculator. This instantly configures the calculator with the exact dimensions recommended for that platform and content type.
Pro Tip
After applying a preset, you can use the resize calculator to scale the dimensions up or down while maintaining the correct aspect ratio for your specific needs.
Compare All Platforms
Click the "Show Comparison Table" button to view a comprehensive table comparing aspect ratios across all platforms. This is useful for content creators who publish across multiple platforms and want to find common ratios that work well everywhere.
Mobile Device Tips
AspectRatioChecker works great on mobile devices with some special features designed specifically for smartphones and tablets.
Using Your Device Camera
On mobile devices, the Upload Image section includes a camera button that allows you to take a photo directly with your device's camera and analyze its aspect ratio immediately.
This is perfect for quickly checking the aspect ratio of physical objects or printed materials.
Touch-Friendly Interface
All controls are optimized for touch interaction with larger tap targets and swipe-friendly navigation.
The comparison table can be scrolled horizontally with a simple swipe gesture.
Add to Home Screen
For quick access, you can add AspectRatioChecker to your device's home screen:
- On iOS (Safari): Tap the share icon, then "Add to Home Screen"
- On Android (Chrome): Tap the menu (three dots), then "Add to Home Screen"
This creates an app-like icon that opens AspectRatioChecker directly, without browser navigation elements.