视频裁剪工具
在浏览器中将视频裁剪为精确尺寸。
Drop your Video file here
or click to browse · max 500 MB
Settings
Crop to 1280x720 starting at (0, 0). Width and height must be even numbers.
128k for speech · 192k for general use · 320k for music
FFmpeg WASM (~25MB) will be downloaded on first use and cached by your browser.
Video Crop
Crops video to a specific rectangular region, removing unwanted edges or areas. Set exact pixel coordinates for the crop area including width, height, and position offset. Useful for removing black bars, focusing on a subject, or creating square videos for social media.
用途
- Removing black bars from videos (letterbox/pillarbox)
- Creating square or portrait crops for Instagram and TikTok
- Focusing on a specific area or subject in the frame
- Removing watermarks or UI elements from screen recordings
- Reformatting landscape video for vertical social media
使用步骤
- Click the upload area or drag and drop your video file
- Set the desired crop Width and Height in pixels
- Set X and Y offset (top-left corner of crop area)
- Click 'Convert to .MP4' to crop the video
- Preview and download the cropped result
工作原理
Upload a video file, set the crop dimensions (width, height) and offset position (X, Y), then click Convert. FFmpeg WASM applies the crop filter and re-encodes with H.264.
技巧与最佳实践
- Width and height must be even numbers for H.264 encoding
- For center crop: X = (original_width - crop_width) / 2
- Social media sizes: 1080x1080 (square), 1080x1920 (portrait), 1920x1080 (landscape)
- Use Video Resize after cropping to scale to a specific resolution
常见问题
How do I know what dimensions to use?
For 16:9 to square, crop to equal width and height. For 16:9 to 9:16 (portrait), swap the dimensions. Common social media sizes: Instagram (1080x1080), TikTok (1080x1920), YouTube (1920x1080).
What do X and Y offset mean?
X is the horizontal offset from the left edge, Y is the vertical offset from the top edge. Both default to 0 (top-left corner). Center crop: set X=(original_width-crop_width)/2 and Y=(original_height-crop_height)/2.
Will cropping reduce file size?
Yes, since you're reducing the number of pixels per frame, the resulting video will be smaller. The exact reduction depends on how much you crop.
隐私与安全
本工具使用编译为 WebAssembly (WASM) 的 FFmpeg。WASM 二进制文件（约 25MB）在首次使用时从 CDN 下载，并由浏览器缓存。所有文件处理均在您的设备上本地完成--您的文件绝不会上传到任何服务器。因此，处理敏感、私密或机密的媒体文件是安全的。较大的文件可能需要更长的处理时间，具体取决于您设备的 CPU 和可用内存。