Rotate video losslessly — or for good
Phones film with the camera sensor in one fixed position and simply note which way up you held them. This rotate video tool can use that same mechanism: the lossless method copies the compressed video untouched and changes only the rotation flag in the MP4 or MOV header, so a 90°, 180° or 270° turn takes a second, whatever the length, with no loss of quality.
Some players, TVs, editors and upload forms ignore that flag and show the clip sideways anyway. For them choose “Re-encode”: every frame is decoded, turned and compressed again, so the picture itself is upright and the flag is cleared. Both methods run in your browser with Mediabunny, an open-source (MPL-2.0) media library; re-encoding uses the browser’s WebCodecs encoders. Nothing is uploaded.
How to use the Rotate Video
- Drop the sideways video on the upload area. The details panel shows its size and, if it already has one, the rotation flag the phone wrote.
- Choose the turn: ↻ 90° right (clockwise), 180° (upside down) or ↺ 90° left (anticlockwise). The preview shows the result.
- Choose Lossless · rotation flag for an instant, quality-preserving fix, or Re-encode · turn the pixels if the video must look right in software that ignores rotation flags.
- Press “Rotate video”. Lossless jobs finish almost at once; re-encoding shows a progress bar with a Cancel button.
- Play the After video to check it, then press Download.
Rotate Video features
Lossless rotation flag
Copies the H.264, HEVC, VP9 or AV1 stream byte for byte and writes a new orientation into the MP4/MOV header — no generation loss, and it works even when your browser cannot decode the codec.
Real pixel rotation
Re-encode mode bakes the turn into every frame for TVs, older editors and sites that ignore orientation metadata.
Works with existing flags
The turn is added to any flag already in the file, and “None” with re-encode turns a flagged phone clip into plain upright pixels.
Preview before saving
A decoded frame shows exactly how the result will look, and the frame slider checks other moments.
Sound untouched
The audio track is copied as it is in lossless mode and kept in re-encode mode (converted to Opus only for WebM).
Private and quick
Runs entirely in the browser — even a long video is rotated without being uploaded anywhere.
Lossless or re-encode: which should I use?
Phones, web browsers, VLC, QuickTime and the big video sites honour the flag, so the lossless method is enough for most people. Choose re-encode when a smart TV, a projector, an older editing program or an upload form still shows the video on its side.
| Lossless · rotation flag | Re-encode · turn the pixels | |
|---|---|---|
| Speed | About a second, any length | Depends on length, resolution and device |
| Quality | Identical to the original | Very slightly lower (one more compression) |
| File size | Practically the same as the original | Depends on the quality setting |
| Players that read the flag | Upright | Upright |
| Players that ignore the flag | Still sideways | Upright |
| Output | MP4 (or MOV for a MOV), original codec | MP4, WebM or MOV in the codec you choose |
Why videos end up sideways
A phone stores video in the orientation of its camera sensor and adds a rotation value — 0°, 90°, 180° or 270° — to the file. If the phone was held at an angle its orientation sensor did not catch (pointing down at a table, for instance), the value is wrong and the clip plays sideways everywhere: rotate it by the missing amount. If it is upright on your phone but sideways on your TV, the flag is right but the TV ignores it: choose “None” with “Re-encode” to bake the existing flag into the pixels.
WebM files have no rotation flag that players reliably follow, so a lossless turn of a WebM is saved as MP4 with the same VP9 or AV1 stream inside. Mirrored rather than rotated footage — text reading backwards — is a job for Flip Video.
Which way is clockwise?
- ↻ 90° right (clockwise): the top of the picture moves to the right-hand side. Use it when people appear lying on their left side.
- ↺ 90° left (anticlockwise, 270°): the top moves to the left. Use it when people appear lying on their right side.
- 180°: for upside-down footage, common from action cameras mounted under a helmet peak or a car mirror.
- Rotating a still photo instead? The rotate and flip image tool does the same for JPG and PNG files, and Crop Video tidies the framing once the clip is upright.
Rotate Video FAQ
How do I fix a sideways video?
Drop it on the page, pick the turn that makes the preview upright (usually ↻ 90° right or ↺ 90° left), keep “Lossless · rotation flag” selected and press “Rotate video”. Download the result and check it in the player you use.
Does rotating a video reduce its quality?
Not with the lossless method: the compressed video data is copied exactly and only a header value changes. The re-encode method compresses the video again, which costs a little detail at “High” quality.
Why is my rotated video still sideways on my TV?
The TV ignores rotation flags. Rotate the original again with “Re-encode · turn the pixels”; the frames themselves are then upright and no flag is needed.
Can I rotate a video 90 degrees without re-encoding?
Yes — that is exactly what the lossless method does. It works for H.264, HEVC, VP9 and AV1 video and saves an MP4 (or a MOV if you started with one).
Can I rotate an iPhone video?
Yes. iPhone MOV and MP4 files are supported, including HEVC. Lossless rotation keeps the original HEVC stream; re-encoding needs a browser that can decode HEVC, such as Safari, or Chrome and Edge on computers with hardware HEVC support.
Is the video uploaded when I rotate it?
No. Both methods run inside your browser tab, and the file never leaves your device.