Resize Video Online Free

Frequently asked questions

How do I resize a video for social media online?

Upload your video (MP4, WebM, or MOV). Choose 9:16 (TikTok/Reels), 1:1 (Instagram), or 16:9 (YouTube). Click "Resize video". FFmpeg.wasm scales and pads in your browser; vertical formats get blurred fill. Download the result. Your file never leaves your device.

Are my videos sent to a server?

No. Resizing runs entirely in your browser using FFmpeg.wasm. Your video never leaves your device.

What do the format options mean?

9:16 (1080×1920) is vertical for TikTok, Reels, Stories; sides get blurred fill. 1:1 (1080×1080) is square for Instagram posts; letterbox gets blurred. 16:9 (1920×1080) is widescreen for YouTube; padding is black if needed.

Why does FFmpeg take a few seconds to load?

FFmpeg.wasm is a large WebAssembly module. It is downloaded once and cached. The first time you use the tool you will see a short loading state.

Does it work on mobile?

Yes, in browsers that support WebAssembly. Resizing may take a while on phones for long or high-resolution videos.

What format is the output?

The output is always MP4 (H.264 video, audio copied) for compatibility with social platforms.

Will quality be reduced?

The video is scaled to fit the chosen size. If your video is smaller than the target it is upscaled (can look soft). If larger, it is downscaled and usually keeps good quality. Blurred areas are generated from the video.

Can I use custom dimensions?

This tool offers three fixed social presets (9:16, 1:1, 16:9). For custom dimensions use a desktop video editor.

Is there a file size limit?

There is no fixed limit. Very long or high-resolution videos may take longer and use more memory. Practical limits depend on your device.

Does it work in all browsers?

FFmpeg.wasm requires a modern browser with WebAssembly. Chrome, Firefox, Safari, and Edge (recent versions) work.