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How to Rotate a Video 90°, 180°, or 270° and Save It Correctly

Fix sideways phone videos with permanent 90/180/270° rotation — via metadata flag (instant) or real re-encode.

Rotation runs locally via Zro7 Rotate Video using ffmpeg.wasm. Personal recordings never leave your browser.

To rotate a video 90°, 180°, or 270° permanently, use Zro7 Rotate Video. Choose fast (flip a metadata rotation flag, instant, no quality loss) or real (physically re-encode rotated frames, universal compatibility). Everything runs in your browser via ffmpeg.wasm; nothing is uploaded.

Metadata flag vs real rotation

  • Metadata flag (fast) — writes a rotation tag in the MP4 header. Compliant players (VLC, iOS, Android, YouTube, most modern software) honor it. Instant, byte-identical pixels.
  • Real rotation (re-encode) — actually rotates each frame's pixels. Every player displays it correctly, including older browsers and embed pipelines. Slower; one generation of encoding loss.

Which to pick

For personal viewing and modern platforms, metadata rotation is enough and preserves quality. For embeds (websites, PowerPoint, older Windows Media Player, some CMSes) that ignore the rotation tag, use real rotation. If unsure and quality tolerance is loose, use real rotation — it always works.

Steps

  1. Open Rotate Video.
  2. Drop the sideways / upside-down video.
  3. Pick 90° CW, 90° CCW, or 180°.
  4. Pick fast (metadata) or real (re-encode).
  5. Click Rotate and download.

Why iPhone videos look sideways in the first place

iPhones always record sensor-native (landscape) and set an orientation tag telling players to rotate. Compliant apps honor it; non-compliant ones (older Windows apps, some web CMSes) don't — hence the "sideways" bug. Real rotation eliminates the ambiguity.

Frequently asked questions

Does metadata rotation affect quality?

No. It only changes a byte in the header.

Which mode does YouTube honor?

Both. YouTube reads the rotation tag; if you re-encoded, they see already-rotated pixels. Either works.

Can I rotate audio?

There's no such thing as sideways audio. Audio streams are copied through unchanged.

Multi-GB files supported?

Yes. Metadata mode is instant regardless of size; re-encoding scales with duration and resolution.

Any upload?

None. Rotation happens in ffmpeg.wasm inside your tab.

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