Aspect Ratio Calculator
Find the aspect ratio of any resolution, or scale dimensions proportionally. Recognizes common presets like 16:9, 4:3, and 1:1.
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Frequently asked questions
What are common aspect ratios for social media?
YouTube / video: 16:9 (1920x1080, 1280x720). Instagram square: 1:1 (1080x1080). Instagram portrait: 4:5 (1080x1350). Instagram Reels / TikTok: 9:16 (1080x1920). Facebook cover: 16:9. Twitter/X header: 3:1. LinkedIn cover: 4:1. Pinterest: 2:3 (1000x1500).
What is the difference between 16:9 and 4:3?
16:9 is widescreen (1.78:1) — standard for modern TVs, YouTube, and most monitors since the late 2000s. 4:3 is near-square (1.33:1) — the old standard for CRT TVs, DVD video, and many tablet screens. A 4:3 video on a 16:9 screen shows black bars on the sides (pillarbox); a 16:9 video on a 4:3 screen shows bars top and bottom (letterbox).
How do I resize an image without distorting it?
Maintain the original aspect ratio by scaling proportionally. This tool calculates the correct height for any target width (or vice versa) so the image is never stretched or squished. To crop to a different ratio, you lose content but avoid distortion. Most editors (Photoshop, GIMP, Lightroom) have a 'constrain proportions' toggle that does this automatically.