Aspect Ratio Calculator | 16:9, Social Media & DPI

Aspect ratio is the proportional relationship between width and height (W:H). Common ratios: 16:9 (widescreen TV/monitors), 4:3 (older TV/photo), 1:1 (Instagram square), 9:16 (mobile Stories/Reels), 21:9 (ultrawide).

If you know the ratio and one dimension, use cross-multiplication: new height = (new width × ratio_height) / ratio_width. Example: scaling a 1920×1080 (16:9) image to 1280 wide: height = (1280 × 9) / 16 = 720. This calculator handles all conversions instantly.

YouTube recommends 16:9 (1920×1080 for Full HD, 3840×2160 for 4K). For YouTube Shorts, use 9:16 (1080×1920). Videos in other ratios will have letterboxing or pillarboxing added by YouTube automatically.

DPI = Pixels / Physical Size (inches). For example, a 3000×2000 pixel image printed at 10×6.67 inches = 300 DPI. Use the DPI mode in this calculator — enter pixel dimensions and target print size to instantly verify print quality.

Yes! In guest mode, you can export your calculations to JSON format. Sign in is required for PDF and CSV export. Click the export button to download your results. This is perfect for record-keeping, sharing with others, or importing into other tools.

Yes! Your calculation history is automatically saved. Guest users can save up to 50 calculations per workspace locally. Sign in for free to save up to 100 calculations per workspace, with access from any device when logged in.

Absolutely! The Aspect Ratio Calculator is completely free with no sign-up required. Create a free account to unlock additional features like more calculation history, multiple workspaces, and the ability to access your saved data from any device.