Rotate video

1. 1

   Add the video

   Drop it in. A still shows how it will look, turned 90° to the right to start.

2. 2

   Pick the turn

   90° right, 180° or 90° left, with a flip if you need one. Keep the orientation tag unless an app shows the video the wrong way round.

3. 3

   Save and download

   Play the result to check it, then download the MP4.

Phones usually store a video the way the camera sensor sees it and add an orientation tag that says how to turn it for playback. When the phone reads its position wrong, often because recording started with it lying flat, the tag is wrong and the video plays sideways everywhere.

Fixing the tag turns the video wherever tags are followed, and nearly every player and site follows them, since nearly every phone video has one. The frames are copied as they are, so it takes a moment and loses nothing.

A few apps ignore the tag and show the video the way it's stored. For those, pick "Into the picture": every frame is turned and encoded again as H.264, which takes longer and comes out close to the original but not identical.

If a video looks right here but sideways in another app, that app is ignoring its tag. Save it "Into the picture" with no turn, and it plays upright everywhere.

The tag works for H.264 and HEVC video, which is what phones record. Other videos, such as VP9 in a WebM, are always saved into the picture.

FFmpeg sets the tag while copying the video with -display_rotation, which counts degrees counter-clockwise, so -90 turns the video right, and replaces any rotation the file already has. The transpose filter turns the picture itself and encodes it again:

• ffmpeg -display_rotation -90 -i input.mp4 -c copy output.mp4
• ffmpeg -i input.mp4 -vf transpose=clock -c:a copy output.mp4

No. It's read and saved in your browser. Nothing is sent anywhere.

Not with the orientation tag, which copies every frame as it is. "Into the picture" encodes the video again at high quality, close to the original but not identical.

It's stored sideways with a tag to turn it, and that app ignores the tag. Save it here "Into the picture", with no turn if it already looks right, and it plays upright everywhere.

No, only by quarter turns: 90° either way or 180°. Those are the turns that fix a video recorded the wrong way round.

Any video your browser can read. H.264 and HEVC, which phones record, can be turned in the tag. Others are turned in the picture and come out as H.264.