Crop Video Online – Change Video Aspect Ratio & Frame Boundaries
Crop video frame dimensions for free. Customize video boundaries directly in your browser.
The Crop Video tool allows content creators, social media marketers, and video editors to alter the visible rectangular frame dimensions of video recordings without desktop editing software. Accepting MP4, WebM, MOV, and MKV inputs, the visual editor overlays an adjustable aspect ratio bounding box across the video canvas, letting you crop widescreen 16:9 landscape footage into 9:16 vertical video for TikTok and Instagram Reels, 1:1 square video for feed posts, or custom focal crops to eliminate unwanted background clutter. The rendering engine utilizes client-side WebAssembly video processing to crop pixel coordinates frame-by-frame and re-encode the audio-video stream cleanly. Users should be aware that cropping a video inherently discards the pixels outside the selection rectangle, so cropping a small sub-section of a 1080p clip will produce an output with lower total pixel resolution than the original.
How to Use Crop Video Online – Change Video Aspect Ratio & Frame Boundaries
Load Source Video Clip
Upload your video file into the player to view the active frame and initialize the bounding crop box overlay.
Position and Scale Crop Boundaries
Select an aspect ratio preset (16:9, 9:16, 1:1, 4:5) or drag the corner crop handles freely to frame your desired visual subject.
Render and Save Cropped Video
Click Crop Video to process the pixel spatial extraction in local memory and download your cropped video file.
Frequently Asked Questions
How do I crop a horizontal YouTube video into a vertical TikTok or Reel?
Select the 9:16 vertical aspect ratio preset, drag the crop box to center your primary subject on screen, and click render to output a mobile-friendly vertical video.
Will cropping a video reduce its visual sharpness?
Cropping removes outer pixels; if you crop deeply into a video, the remaining resolution is smaller than the original. Our encoder uses high-bitrate settings to keep the remaining pixels crisp.
Is audio synchronized properly after cropping video frame bounds?
Yes. The audio stream is copied and remuxed with frame-accurate timestamp synchronization, ensuring voices and music stay perfectly in sync.
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