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Free Video Aspect Ratio Tool
Horizontal ↔ vertical in one click. TikTok-ready.
Convert a horizontal YouTube video to a vertical TikTok / Reels / Shorts clip — or square Instagram, 4:5 portrait, or any other aspect ratio — without re-shooting. Smart cropping keeps the most important part of the frame in view, and you can fine-tune the crop position before export. No watermark, browser-based, free forever.
How Video Aspect Ratio Tool works
- 1
Upload your video
Drag and drop an MP4, MOV, WebM or M4V file (up to 100 MB).
- 2
Pick the target aspect ratio
9:16 (TikTok / Reels / Shorts), 1:1 (Instagram square), 4:5 (Instagram portrait), 4:3 (legacy TV), or 16:9 (YouTube). Adjust the crop position with the visual preview.
- 3
Download the reframed clip
Conversion runs in seconds. The output respects the new aspect ratio with the original quality and audio preserved.
Why CinobiLabs
- All major platforms covered — 9:16, 1:1, 4:5, 4:3, 16:9
- Manual crop-position override for off-centre subjects
- No watermark, original quality preserved
- Truly free — no monthly limit on conversions
Frequently asked questions
Will the video lose quality when reframed?
Cropping itself is lossless — we re-encode at the same bitrate as the source so visual quality stays close to the original. The output dimensions follow the new aspect ratio at the source's native resolution.
Can I add letterboxing instead of cropping?
Yes — pick "Fit (letterbox)" in the export options to preserve the entire original frame inside black bars. Default is "Crop" because that's what TikTok / Reels expect.
Which aspect ratios do you support?
9:16, 1:1, 4:5, 4:3, 16:9. These cover every major platform: TikTok, Instagram Reels, Instagram Feed (square + portrait), YouTube Shorts, Twitter, LinkedIn, Facebook, and traditional 16:9 web video.
How does the smart cropping decide what to keep?
By default we centre-crop, which works for talking-head and centred subjects. For off-centre subjects, manually drag the crop position before export — the preview updates live.
Can I use this for a multi-person interview shot in 16:9 → 9:16?
Yes, but you'll lose half the frame. For multi-person 9:16 conversion you might want to crop the speaker only, or split the source into two vertical clips and switch between them — common technique for podcast clips on TikTok.
Do you store my videos?
Files are held in temporary storage for 24 hours so you can re-download, then deleted automatically.
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