Rotate Video

Fix a sideways clip by rewriting its rotation flag, which is instant and lossless, or bake the rotation into the pixels for stubborn players.

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Drop your file here (.mp4, .mov, .m4v)

🔒 Private by design: your files are processed locally in your browser and never uploaded to any server.

Written and maintained by Last updated

Sideways video is metadata, not pixels

A phone records in one orientation regardless of how you hold it. What changes when you turn the handset is a small piece of metadata written alongside the video, a matrix telling any player how far to rotate the picture before showing it.

That design is efficient and it is why sideways clips exist. Every mainstream player reads the flag and does the right thing. Then the clip goes through an upload pipeline, an editor, or a player that ignores it, and suddenly your subject is lying on their side.

There are therefore two entirely different ways to rotate a video, and the choice between them is the whole content of this tool. Rewrite the flag, which is instant and lossless but depends on the player cooperating. Or turn the pixels, which is slower and costs a small amount of quality but leaves nothing to interpret.

Fixing a sideways clip

  1. Drop your video on the box or use Choose a file. MP4, MOV and M4V are accepted.
  2. Choose a Rotation. The three options turn the picture a quarter turn clockwise, a half turn, or a quarter turn anticlockwise.
  3. Leave Method on Fast, rotate without re-encoding (recommended) unless you already know your target ignores rotation flags.
  4. Click Rotate Video.
  5. Download the result. It keeps its original container, with a rotated suffix added to the name.
  6. Check it in the player you actually care about, not just in the browser.
  7. If it still looks wrong there, run it again with Re-encode pixels (maximum compatibility).

The fast path finishes in seconds even on a large file, because nothing is decoded. The re-encode path takes as long as encoding the clip normally would.

What the fast path actually does

Before writing anything, the clip is probed and its current rotation flag is read out of the stream information. That value matters, because in this engine writing a new rotation replaces the existing one rather than adding to it.

So the number written is computed by composing the two. A clip already flagged at a quarter turn, asked for a further quarter turn clockwise, gets the combined value rather than the value you selected. Without that composition step, rotating an already-rotated phone video would silently reset it instead of turning it.

Everything else is copied through byte for byte, and the file is written so that a player can begin before the whole file has arrived, which matters when the result is going to be streamed.

When the fast path gives up

Two things can go wrong, and both are handled without asking you.

The stream copy can fail outright, because not every container and codec combination will accept a rewritten rotation flag. Or it can appear to succeed and produce an empty output file, which is the failure mode that would otherwise hand you a zero byte download.

Both cases are detected and the tool falls back to the physical rotation path automatically. The quarter turns use a transpose operation, one variant per direction, and the half turn is done as a horizontal flip followed by a vertical one, which is exactly equivalent and cheaper. Video is re-encoded at a quality-leaning setting; audio is copied without being touched.

If the problem is a mirror image rather than an orientation, Flip Video is the tool, and mirroring is a genuinely different operation from rotating even though both are one click.

For reframing rather than turning, Crop Video trims to a region and Resize Video for Social Media targets a platform aspect ratio directly. If your file is a container this tool does not accept, MOV to MP4 and MKV to MP4 will convert it first. And when a rotated clip is one piece of a longer edit, Merge Videos joins them. The rest is on the video tools hub.

Frequently asked questions

How can rotating be lossless?

Because in the fast method nothing is rotated. Every MP4 and MOV can carry a rotation flag telling the player how to display the picture, and the fast path rewrites that flag while copying the video and audio through untouched. No frame is decoded and none is re-encoded, so the result is bit for bit identical apart from the flag, and it finishes in about as long as it takes to copy the file.

Why does the fast method sometimes fail?

Not every combination of container and encoder accepts a rewritten rotation flag, and a stream copy into a container that will not hold it fails outright. That case is caught. If the fast attempt errors, or produces an empty output file, the tool falls back automatically to physically rotating the pixels. You do not have to notice or retry.

Why does my clip still look sideways in some players?

Because the rotation flag is a hint and some software ignores it. Browsers, phones and every mainstream player honour it, but older editors, some upload pipelines and a few embedded players do not. If your target is one of those, pick the re-encode method, which turns the pixels themselves and leaves nothing to interpret.

My phone video was already rotated. Does that get double counted?

No, it is composed rather than added blindly. The clip is probed first for any existing rotation flag, and the new value is calculated relative to it. A video already flagged as rotated a quarter turn, asked to go a further quarter turn clockwise, ends up flagged at the correct combined angle rather than at the angle you asked for alone.

Does the re-encode method lose quality?

A little, unavoidably, since the frames are decoded and encoded again. The setting used leans toward quality rather than file size, on the reasoning that you asked for a rotation and not for compression, so the loss is small. Audio is copied through without being touched at all, so only the picture is affected.

How is a 180 degree turn done?

By flipping horizontally and then vertically, which is exactly equivalent to turning the frame upside down and avoids a rotation step. The quarter turns use a transpose operation instead, one variant for each direction. All of this only applies to the re-encode path; the fast path just writes a number.

What container do I get back?

The same one you put in. Unlike most video tools here, the rotation is written back into the original container, so a MOV stays a MOV and an MP4 stays an MP4. The output name gains a rotated suffix and the extension comes back in lower case, so a file named with a capitalised extension returns with a lower case one.

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