OneTaskBy Tim King · Updated
Video Rotator
Rotate a Sideways or Upside-Down Video by 90 or 180 Degrees, Keeping Sound
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How the Video Rotator works
This video rotator turns a sideways or upside-down clip the right way up, or mirrors it left to right. Pick the change, press Render and download a fixed copy with its sound. The rotation is done in your browser, so the video never leaves your computer.
Sideways video is almost always a phone's fault. The orientation sensor locks a moment late, or the phone was flat on a table when recording started, and the clip comes out on its side. Some players read a rotation flag in the file and fix it on screen, but many editors, upload forms and older TVs ignore the flag and show it sideways anyway.
How the video rotator works
Your browser decodes the clip, already applying any rotation flag the phone stored, so what you see in the preview is what gets rotated. Each frame is drawn onto a canvas through a rotation or mirror transform and recorded with MediaRecorder, along with the original audio. For the two 90° options the canvas swaps its width and height, so a 1920 × 1080 clip becomes 1080 × 1920.
The output has the rotation built into its pixels, with no flag to be misread. It will play the right way up everywhere.
Which option to pick
| The preview shows | Choose |
|---|---|
| Top of the picture on the left | 90° clockwise |
| Top of the picture on the right | 90° anticlockwise |
| Upside down | 180° |
| Text reads backwards (selfie camera) | Flip horizontally |
| Reflected, as in water | Flip vertically |
Rotate or flip?
Rotating turns the whole picture around its centre, so nothing is mirrored and text stays readable. Flipping is a mirror image. Front cameras on many phones save a mirrored picture, so signs and T-shirt slogans read backwards. Flip horizontally fixes that. A vertical flip on its own is rarely what people want; 180° is usually the fix for an upside-down clip.
Tips and pitfalls
Check the preview first. If the preview player above already shows the clip upright, the file is fine and only the app you used is ignoring its rotation flag. Rotating it again would turn it sideways.
Rotating a landscape clip makes it vertical. That is right for a phone held the wrong way, but on a TV it will be pillarboxed. The square and story padder can put it in a landscape frame.
The render is real time. A 90-second clip takes about 90 seconds; keep the tab in front.
How to read the result
The stats show the source size, the output size after any width and height swap, the change applied and the new file size.
FAQ
Why is my phone video sideways?
Phones record the sensor in landscape and store a rotation flag saying how to show it. If the phone guessed wrong, or an app ignores the flag, the video appears sideways. Rotating it here fixes the pixels themselves, so every player agrees.
Does rotating a video lose quality?
A little. The picture is re-encoded at about 6 Mbit/s, which looks close to the source for phone footage. Rotation itself is exact at 90° steps, so no pixels are blurred or cropped.
Is the sound kept?
Yes, unless you choose Remove. The audio is recorded alongside the rotated picture, in sync, at your browser's standard audio quality. The original audio track is not copied byte for byte.
Is my video uploaded to rotate it?
No. The rotation is done by your browser on your device. Nothing is sent anywhere, which also means the file size you can rotate is limited only by your computer.
See also: all Video & Screen tools, Images, Audio, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
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