Free Online Aspect Ratio Calculator — 16:9, 4:3, 21:9 — QuizOxa Tools
Calculate proportional width or height dimensions for videos, digital displays, images, and responsive web containers. Select popular presets like 16:9 widescreen, 4:3 SD, 9:16 mobile story, or enter custom ratio proportions.
Aspect Ratio Proportions
Target Dimensions (Pixels)
padding-top: 56.25%;aspect-ratio: 16 / 9;Common questions
What is aspect ratio?
Aspect ratio expresses the proportional relationship between an image or display screen's width and height (Width : Height).
Which aspect ratio should I use for social media?
16:9 is ideal for YouTube/desktop videos, 9:16 for vertical TikTok/Instagram Reels, 1:1 for Instagram feed posts, and 4:5 for mobile vertical photos.
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