Rotate or flip a video
Choose an MP4 or MOV, turn it 90° left or right, 180°, or mirror it, and download a new MP4. For a plain turn you can choose to change only the rotation flag: instant, with no quality loss. Or redraw the picture so that every player and app shows it the right way up.
Drop a video here
MP4, MOV or M4V up to 1 GB. Nothing is uploaded.
How it works
- •Choose or drop a video. The preview shows it the way players show it now.
- •Press the turn and mirror buttons until the preview looks right.
- •Choose how to save it. "Only change the rotation flag" rewrites a few bytes in the original file that tell players how to turn the picture, which is how phones store portrait video; nothing else changes. "Redraw the picture" turns the pixels themselves and re-encodes them as H.264 in a new MP4, for apps that ignore the flag.
- •Download the result: an MP4 when redrawn, or a copy of your file with its own type (MP4 or MOV) when only the flag changed. The original file is not changed.
- •The file is read with mp4box.js and written with mp4-muxer, two open-source libraries served from this site (licences: /tools/vendor/NOTICE-media.txt). Decoding and encoding use your browser's own WebCodecs; nothing is sent anywhere.
What it does and what it cannot do
- •Reads MP4, MOV and M4V up to 1 GB with H.264 video (HEVC from phones only where your browser can decode it). WebM, MKV and AVI are not supported.
- •Needs a browser with WebCodecs and an H.264 encoder: recent Chrome or Edge on a computer, Safari 16.4 or later, or Firefox 130 or later. The page checks first and says so if yours cannot.
- •Turns are in steps of 90°. Straightening a slightly tilted video is not possible here.
- •Mirroring cannot be stored as a flag, so a mirrored video is always redrawn and re-encoded, which loses a little quality.
- •The rotation flag is respected by almost every player and browser, but some older apps, a few editing programs and some upload sites ignore it.
- •The flag-only mode works in any modern browser and with any video format in an MP4 or MOV, and keeps the recording date and other details. Redrawing needs a WebCodecs browser and does not copy that metadata.
Questions
- Is my video uploaded?
- No. Your browser does the work and saves the result; nothing is sent anywhere.
- Which mode should I pick?
- Try "Only change the rotation flag" first: it takes seconds and keeps full quality. If the app you share to still shows the video sideways, use "Redraw the picture".
- Why is my phone video sideways on my computer?
- Phones record in landscape and add a rotation flag for portrait videos. An app that ignores the flag shows the raw sideways picture. Redrawing the picture upright fixes it for every app.
- Can I mirror a selfie video?
- Yes. Press "Mirror left-right". The picture is redrawn, so it works everywhere.
- Does rotating lose quality?
- Not in flag mode: only the flag bytes change, the picture is untouched. When the picture is redrawn it is re-encoded at about the original bitrate, which loses a little.
- Can I rotate by 45 degrees?
- No, only in 90° steps. Turning by other angles would need cropping or borders; this tool does not do that.