Calculate image aspect ratios, resize dimensions, and crop coordinates. Convert between common photo, video, and social media aspect ratios.
Aspect ratio is the proportional relationship between an image's width and height. It determines how an image fits different displays, prints, and social media platforms. Getting aspect ratios wrong leads to unwanted cropping, letterboxing, or distorted scaling that can ruin the visual impact of photos and videos.
This calculator handles all aspect ratio tasks: compute the ratio from pixel dimensions, find missing dimensions when constraining to a specific ratio, calculate crop coordinates, and convert between common ratios. It covers photography standards (3:2, 4:3), video formats (16:9, 21:9), social media requirements (1:1 for Instagram, 9:16 for Stories/Reels), and print sizes (5:7, 8:10).
The tool is invaluable for photographers preparing images for multiple platforms, graphic designers creating assets at various sizes, and videographers ensuring their footage matches delivery specifications. Enter your source dimensions and target ratio, and it instantly shows the resulting size, whether you need to crop or pad, and exactly how many pixels are affected.
Beyond simple ratio conversion, the calculator also computes megapixel counts, file size estimates, and PPI (pixels per inch) for print, making it a one-stop tool for any image dimension question.
Managing aspect ratios across different platforms and print sizes is a constant challenge for photographers and designers. This calculator eliminates math errors and shows exactly what you gain or lose when converting between formats. Keep these notes focused on your operational context. Tie the context to the calculator’s intended domain. Use this clarification to avoid ambiguous interpretation.
Aspect Ratio = GCD-reduced W:H. New Width = Height × (target_W / target_H). New Height = Width × (target_H / target_W). Megapixels = (W × H) / 1,000,000.
Result: 6000 × 3375 (crop to 16:9)
A 6000×4000 image (3:2) cropped to 16:9 becomes 6000×3375, removing 625 pixels from top and bottom (15.6% height loss). The result is 20.25 megapixels.
**Photography:** 3:2 (DSLR standard), 4:3 (compact/phone), 1:1 (square), 5:4 (8×10 print), 7:5 (5×7 print). **Video:** 16:9 (HD/4K), 21:9 (cinema wide), 4:3 (classic TV), 2.39:1 (anamorphic). **Social Media:** 1:1 Instagram squares, 4:5 Instagram portrait, 9:16 Stories/TikTok, 1.91:1 Facebook/Twitter landscape.
When you crop from 3:2 to 16:9, you lose 15.6% of the image height. From 3:2 to 1:1, you lose 33% of the width. Understanding these numbers helps you compose with future crops in mind. A "loose" composition with extra space around the subject gives maximum flexibility for multi-platform delivery.
**Web/Social:** 72 PPI convention, but actual pixel dimensions matter more. Instagram max is 1080×1080 (square), 1080×1350 (portrait). **Print:** 300 PPI for photo-quality, 240 PPI minimum acceptable. A 24-megapixel camera (6000×4000) prints at 300 PPI up to 20×13.3 inches. **Large Format:** Billboard and signage can use much lower PPI (50-150) because viewing distance is greater.
3:2 is the standard for DSLRs and 35mm film. 4:3 is standard for smartphones and Micro Four Thirds cameras. 1:1 is used by some medium format cameras.
4K UHD (3840×2160) and 4K DCI (4096×2160) are both 16:9 (approximately). DCI 4K is slightly wider at 1.9:1.
Start with the highest resolution source possible. Cropping away 20-30% of pixels is usually acceptable. Beyond that, the loss may be visible in large prints.
1:1 (square), 4:5 (portrait), or 1.91:1 (landscape). Stories and Reels use 9:16 vertical format.
Yes. 16:9 (1.78:1) is the standard widescreen format for HD/4K video and most monitors. Ultra-widescreen is typically 21:9 (2.33:1).
PPI = pixels / print dimension in inches. For sharp prints, aim for 300 PPI. A 6000px wide image prints sharp at 20 inches wide.