How to flip a video
1. Drop the clip. 2. Leave Horizontal for a mirror (left and right swap) or choose Vertical to turn the picture upside down. 3. Press “Flip video” and download the MP4.
Width and height stay the same. Use horizontal when a screen recording or a selfie looks reversed. Use vertical when the clip was saved upside down and a 180° rotate is not what you want.
Mirror is not the same as rotate
Rotate turns the frame and can swap width and height. Flip reflects it. Text in the picture will read backwards after a horizontal mirror, which is what you want for a true mirror and wrong if you only needed the clip upright. For that, use Rotate video.
Sound, length and privacy
The audio is encoded again as AAC and stays lined up with the picture. The duration does not change. Encoding uses one CPU thread, so a one-minute clip can take a minute or more. The file is not uploaded.