How to rotate a video
1. Drop the clip that was saved sideways or upside down. 2. Choose 90° clockwise, 90° counter-clockwise or 180°. 3. Press “Rotate video” and download the MP4.
A quarter turn swaps width and height. 180° keeps the same pixel size. Phone clips that play on their side are the usual case: one 90° turn stands the picture up.
The turn is in the pixels
GustKit re-encodes the picture with FFmpeg so the new file is already upright. Players that ignore a rotation flag still show it the right way. The audio is encoded again as AAC and stays in sync. A clip that already looks upright does not need this page.
What this page does not do
It turns the whole frame, not a crop. To cut a region, use Crop video. To turn a still photo, use Rotate image. To turn pages inside a PDF, use Rotate PDF. Long clips are limited by the time shown next to the button, because encoding uses one CPU thread.