Convert Horizontal Video
to Vertical & Back
Free — No Upload Required
Convert horizontal video to vertical for TikTok, Instagram Reels & YouTube Shorts — or convert vertical video to horizontal for YouTube & presentations. 100% free, no watermark, processed in your browser.
Convert Video Aspect Ratio for Every Platform
Convert horizontal video to vertical for social media, or vertical to horizontal for desktop — works with every major platform.
TikTok
9:16
Instagram Reels
9:16
YouTube Shorts
9:16
YouTube
16:9
16:9
16:9
Twitter/X
16:9
Presentations
16:9
How to Convert Video Aspect Ratio Online
Convert horizontal to vertical or vertical to horizontal in three simple steps — no software download needed.
Choose Your Mode
Select whether you want to convert from horizontal to vertical (16:9 → 9:16) or vertical to horizontal (9:16 → 16:9).
Upload Your Video
Drag and drop your video file or click to browse. We support MP4, WebM, MOV, and more. Files are processed locally in your browser.
Download Result
Your converted video is ready in seconds. Preview it and download the MP4 file. No watermarks, no sign-up required.
Best Free Video Aspect Ratio Converter
The fastest, most private way to convert video from horizontal to vertical or vertical to horizontal online.
100% Privacy
Your videos are processed entirely in your browser using WebAssembly. Nothing is uploaded to any server.
No Watermark
Unlike other tools, AspectFlip never adds watermarks to your converted videos. The output is clean and professional.
Completely Free
No hidden fees, no premium tiers, no credits system. Convert as many videos as you want, forever.
Smart Background Fill
Videos are converted with a clean black background, keeping the original content centered and clearly visible.
Works Offline
Once loaded, the converter works without an internet connection. Perfect for on-the-go content creation.
All Formats Supported
Import MP4, WebM, MOV, AVI, and MKV files. Export as optimized MP4 with H.264 encoding for maximum compatibility.
Frequently Asked Questions
Everything you need to know about converting video aspect ratios.
Is AspectFlip really free?
Are my videos uploaded to a server?
What video formats are supported?
How does the conversion work?
Is there a file size limit?
What aspect ratios are supported?
Will there be a watermark on my video?
Can I use AspectFlip on my phone?
The Complete Guide to Video Aspect Ratio Conversion
What is Video Aspect Ratio?
Video aspect ratio is the proportional relationship between a video's width and height. The most common aspect ratios are 16:9 (widescreen/horizontal) and 9:16 (portrait/vertical). With the rise of mobile-first platforms like TikTok, Instagram Reels, and YouTube Shorts, vertical video (9:16) has become essential for content creators.
When to Convert Horizontal to Vertical
Converting horizontal (landscape) videos to vertical (portrait) format is necessary when you want to repurpose existing 16:9 content for vertical-first platforms. This is perfect for taking YouTube videos, movie clips, or screen recordings and adapting them for TikTok, Instagram Reels, YouTube Shorts, or Snapchat Stories.
When to Convert Vertical to Horizontal
Converting vertical (portrait) videos to horizontal (landscape) format is ideal when you need to use phone-recorded content in presentations, YouTube videos, websites, or any platform that favors widescreen display.
How AspectFlip Works
AspectFlip uses FFmpeg compiled to WebAssembly (WASM) to process videos entirely in your browser. When you upload a video, it never leaves your device — all processing happens locally using your computer's CPU. The output is encoded as H.264 MP4 for maximum compatibility across all platforms and devices.