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Rotate and speed up a video

Rotate, flip, speed up, slow down or reverse a video.

Drop the video to rotate or change its speed

or click to choose (.mp4, .m4v, .mov, .webm, .mkv, .avi, .wmv, .mpg, .mpeg, .3gp, .flv, .ts, .ogv), or paste from the clipboard (Ctrl+V). Up to 100 MB per file.

Useful for a portrait phone recording that plays on its side.

Mirroring fixes front-camera footage where text reads backwards.

The audio is retuned along with the picture, so voices do not turn into chipmunks.

Without audio the result is smaller and finishes faster.

Reversing loads the whole video into memory. Suitable for short clips up to half a minute; longer ones can run the browser out of memory.

Nothing is changed yet. The video will only be re-encoded to MP4 with practically the same quality.

The video is processed in your browser, nothing is uploaded. The first run downloads about 32 MB of the computing core, after that everything runs without waiting. Longer files take a few minutes.

More about Rotate and speed up a video

How rotating and changing the speed of a video works

Drop the video in, pick a rotation, a flip or a speed and apply the changes. The result is saved as MP4 with the H.264 codec, which plays on phones, computers and TVs alike. The original file stays untouched.

Everything runs through ffmpeg compiled to WebAssembly, right in your browser. The video is never uploaded, and once you close the page nothing of it remains.

  • Rotate 90° clockwise, counter-clockwise or by 180°, typically for a portrait recording.
  • Flip horizontally (mirror) or vertically, for example front-camera footage.
  • Slow down to a quarter or speed up to four times, with the audio retuned to match.
  • Play backwards, suitable for short clips.
  • Remove the audio track when you do not want it in the result.

Frequently asked questions

Does the quality suffer?

The picture is re-encoded, so a little, but you will not notice the difference in normal viewing. We encode at CRF 23, the usual standard for web video. The file size is usually similar to the original and often smaller for phone recordings.

Why is the video re-encoded instead of just rotated?

Phones store rotation only as a note in the file header and every player honours it differently. Actually rotating the picture works everywhere, but it needs a fresh encode. That is why it takes a while: a minute of video takes roughly a minute.

What happens to the audio when the speed changes?

The audio speeds up or slows down together with the picture, but the pitch stays the same. Speech remains intelligible and does not sound like a cartoon. At four times the speed a voice is hard to follow, though.

How long a video can be played backwards?

Reversing has to load every frame into memory, and the browser has a limited amount. Short clips up to half a minute in Full HD go through without trouble; longer ones may end with an error. Trim a longer video first with the video trimming tool.

Which formats can I upload?

MP4, MOV, WebM, MKV, AVI, WMV, MPG, 3GP, FLV, TS and OGV. iPhone videos in the HEVC codec are decoded too, they just take a little longer. The result is always MP4; for another format use the video conversion tool.

Is the video uploaded to a server?

No. The whole computation runs in your browser, and neither the file nor any part of it leaves your device. The first run downloads about 32 MB of the processing engine, after that everything runs without waiting.

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