Image Size Calculator
Select a social media preset or enter custom dimensions. Instantly see the aspect ratio, megapixel count, estimated file sizes, and a scaled visual preview.
Quick Presets
Dimensions
Estimated File Sizes
Visual Preview
Preview is proportionally scaled to fit. Not actual pixel size.
Common Social Media Image Sizes
| Platform | Image Type | Dimensions | Ratio |
|---|
How to Use the Image Size Calculator
This free image size calculator helps you determine the perfect dimensions for any image — whether it's for social media, web design, or print. Select a platform preset to instantly load recommended sizes, or enter custom width and height values to analyze any dimensions.
The calculator automatically computes the aspect ratio, total pixel count, megapixel rating, and estimated file sizes across JPEG, PNG, and WebP formats. The visual preview shows a proportionally scaled representation of your chosen dimensions so you can see the shape at a glance.
Understanding Aspect Ratios
An aspect ratio is the proportional relationship between an image's width and height. Common aspect ratios include 1:1 (square, used by Instagram posts), 16:9 (widescreen, used by YouTube thumbnails), 4:5 (portrait, recommended for Instagram feed), and 9:16 (vertical video, used by TikTok, Reels, and Stories). Matching the correct aspect ratio prevents cropping and ensures your content displays as intended on each platform.
Image Format Comparison
JPEG is the most widely supported format with good compression, ideal for photographs. PNG supports transparency and lossless compression, best for graphics and screenshots. WebP offers superior compression at comparable quality — often 25-35% smaller than JPEG — and is supported by all modern browsers. For social media, JPEG and WebP typically offer the best balance of quality and file size.