Each size is either the platform's own published recommendation or a print size converted at 300dpi. Platforms change their specs without notice, so confirm against the official guidance before anything that matters.

Reels, Shorts, and Stories share 1080x1920, but each covers a different part of the frame with its interface. Picking a preset also turns on a safe area guide that marks those regions in grey. The guide never ends up in the saved file.

An original smaller than the spec is never scaled up. The shortfall is filled with a background you choose, so only the pixel count changes. An original larger than the spec is cropped or scaled down to fit. Enlarging is the only step that costs quality, and it is the one this tool avoids.

The Naver blog header and the 640x640 profile picture have no published specification, so the table lists the working sizes in common use. For a size not in the table, type the width and height directly in the editor.