Crop a Video
Pick a video, set a crop size (and optional offset) — it's cropped in your browser, nothing is uploaded.
Crop a video
Pick a video, set the crop width and height, and (optionally) an x/y offset for the top-left corner — leave the offset blank to crop from the center. The video is re-encoded right in your browser with ffmpeg; nothing is uploaded.
How it works
- Width / height — the size of the rectangle to keep, in pixels.
- X / Y offset — where the rectangle starts from the top-left. Leave both blank to center the crop.
- The output is re-encoded with H.264 video + AAC audio. An mp4, mov, m4v, or mkv keeps its container; other inputs (webm, …) come out as MP4.
Notes
- Cropping re-encodes the video, so very large files take longer (everything runs locally on your machine).
- Want to shrink the file instead of changing its frame? Use the video compressor. Want to cut its length? Use the video trimmer.
FAQ
What happens if I fill in only the X offset (or only Y)?
The moment either offset is set, the crop stops being centered: the missing
offset defaults to 0 (the top or left edge). So x=100 with an empty Y crops
100 px from the left but starts at the very top. Leave both offsets blank if
you want the crop centered on the frame.
Does cropping change the video's format or quality?
An .mp4, .mov, .m4v, or .mkv keeps its container; anything else (a
.webm, …) is converted to MP4, since those containers can't hold H.264/AAC.
Either way the streams are re-encoded to H.264 video + AAC audio — cropping
can't be done without re-encoding. Re-encoding introduces a small generational
quality loss, so crop once from the original rather than repeatedly re-cropping
outputs.
Is my video uploaded?
No — the ffmpeg engine runs in your browser tab; the file never leaves your device.
What if my crop is bigger than the video?
ffmpeg will reject an out-of-bounds crop; pick a width/height/offset that fits within the source dimensions.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool video-crop 'url=https://example.com/input' 'width=640' 'height=360'New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/video-crop/?url=https://example.com/input&width=640&height=360Machine-readable descriptor: tool.json — title + parameters JSON Schema for agents.