Crop Video Online
Processing entirely on your device — large files may take a moment.
Enter the width and height you want in pixels, then anchor the crop — center for talking heads, top for scoreboard banners, left or right for off-center subjects. The crop window is cut from the frame for every second of the clip.
Cropping removes pixels permanently, which is different from resizing — cropped output is smaller in both dimensions and cannot be restored. The output keeps your input container.
How to crop video
- 1
Select your files
Drag & drop your MP4 files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to MP4". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted MP4 file individually, or grab everything at once as a ZIP archive.
About the MP4 format
MP4 (MPEG-4 Part 14) is the universal delivery container of digital video. It wraps H.264, HEVC or AV1 video with AAC audio, and its structure — separate metadata (moov) and media atoms — is what makes streaming, seeking and fast-start playback possible. Phones, cameras, TVs, browsers and every social platform assume MP4 first.
Quality is entirely a function of the codec and bitrate chosen at encode time, so an MP4 can be a 10 Mbps HEVC master or a postage stamp. That flexibility plus total playback coverage is why nothing has displaced it in twenty years — conversion between formats almost always ends in MP4.
+Strengths
- ✓Plays on every device and platform in existence
- ✓Streaming-ready structure (fast start, seeking)
- ✓Choice of modern codecs: H.264, HEVC, AV1
!Limitations
- −Quality depends entirely on encode settings
- −HEVC variants hit licensing gaps on some platforms
Frequently asked questions
Can I crop to a specific aspect ratio like 9:16?
Yes — enter any W×H pair, e.g. 1080×1920 for vertical. Make sure the numbers fit inside the source frame, or the encoder will refuse.
Does cropping reduce quality?
The kept region is re-encoded once at high quality (CRF 23). Pixels inside the crop window are as sharp as the source allowed.
What if I only need a smaller file?
Use the resize tool instead — scaling down keeps the whole picture and shrinks the file honestly.