How to use Video Frame Cropper: settings and output checks
Learn the real workflow, parameters, device limits, privacy, and checks before downloading from Video Frame Cropper.
When to use it
Enter crop X, Y, width, and height to remove video edges and export MP4. Cropping permanently discards areas and requires re-encoding. Coordinates are computed after orientation, and encoder alignment can adjust edges to even pixels.
Practical example
When cropping landscape to 9:16, scrub the timeline to keep the subject in frame. A fixed crop does not track a moving person.
Steps
- Choose video and read its source dimensions.
- Enter crop X, Y, width, and height.
- Set quality and audio bitrate, then process.
- Inspect actual crop bounds, subject placement, and output dimensions.
Choosing parameters
- Crop X
- Crop Y
- Crop width
- Crop height
- Quality / CRF
- Audio bitrate
Test a short or lower-resolution sample first. Do not raise bitrate, sample rate, frame rate, or resolution merely to look “clearer”; re-encoding cannot recover information missing from the source.
Checks before download
- Adapts landscape, square, and vertical framing
- Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task.
Play the complete result and inspect first/last frame, sync, orientation, dimensions, sound, color, and duration. Retest formal deliverables on the target phone, browser, or platform.
Real limits and device requirements
- Discarded regions cannot be restored
- No draggable region, aspect preset, or subject tracking is currently provided
- Crop coordinates must fit the source and dimensions must be even
FFmpeg WebAssembly in a browser depends on device CPU, memory, and bundled codecs. It is not native desktop FFmpeg performance and does not support every codec sharing an extension. Keep the page active; phones, long/high-resolution media, and large files fail more easily.
Privacy and licensing
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task.
The ffmpeg.wasm wrapper is MIT, while the bundled FFmpeg core for this release is distributed under GPL-2.0-or-later. License notices and corresponding source access must remain public. Process only media you are entitled to use.
Common questions
Why does the subject leave the frame later?
The current crop is fixed and does not track people or objects.
Why is an edge one pixel different?
Encoder pixel formats often require even bounds and use safe alignment.
Is video uploaded?
Media is read and transcoded in this browser tab and is not uploaded to FreeTool to perform the task.