Glossary · Getting Started
Quick answer
Aspect ratio is the width-to-height proportion of a video or image. The three you will use most: 16:9 (landscape, YouTube and web), 9:16 (vertical, TikTok, Reels, and Shorts), and 1:1 (square, feed posts). Choosing the right aspect ratio at generation time avoids cropping or letterboxing later, so set it before you generate, not after.
Each platform rewards its native format: vertical 9:16 video fills a phone screen on TikTok and Instagram Reels, while 16:9 suits YouTube, presentations, and embedded web players.
AI video models compose the scene for the ratio you request — a 9:16 generation frames subjects vertically rather than just cropping a widescreen shot — which is why generating in the target ratio beats converting afterward.
Most VdoBloom video tools let you pick the aspect ratio per generation, so the same prompt can be produced as a vertical short and a landscape cut.
VdoBloom starts you with 10 free credits — enough to put this into practice with no card required.
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