Change Video Aspect Ratio
Runs locally in your browser. Nothing leaves your device.Change a video's aspect ratio in your browser. Choose fit or fill, resolution, quality and audio.
Aspect ratio
Place a video into a new aspect ratio without it leaving your device.
Preview
No video selected yet.
How it works
- 1
Select a video
Select a local video file in one of the supported formats.
- 2
Choose the aspect ratio and mode
Choose an aspect ratio or custom values, and contain or cover with position and zoom.
- 3
Download the adjusted video
Review the output plan and download the video with the new aspect ratio.
Good to know
The aspect ratio changer adapts a video to a new format such as 16:9, 9:16, 1:1, or a custom ratio directly in your browser. In “contain” mode, the entire image stays visible and bars may appear; in “cover” mode, the video fills the frame completely and is cropped, controlled via position X/Y and zoom.
A custom ratio can be defined via width and height as numerator and denominator. Filling can cut off image areas, while fitting creates bars — which mode fits depends on the image content and the target platform.
Typical use cases
Fill a landscape video for story formats
Use “cover” mode with position and zoom to bring a 16:9 video edge-to-edge into 9:16 without bars.
Keep the full picture without cropping
Choose “contain” when important content such as subtitles or graphics must not be cut off — bars appear at the edges instead.
Tips for better results
Adjust position and zoom in cover mode
Move the X/Y position and adjust the zoom to hit exactly the desired frame in cover mode.
Define a custom ratio for special formats
Enter custom values for width (numerator) and height (denominator) when none of the presets fit the target platform.
Features
Contain or cover
Choose between a fully visible image with bars or an edge-to-edge crop.
Controllable position and zoom
In cover mode, position X/Y and zoom can be adjusted for the desired frame.
Local processing
Your video never leaves your device; the adjustment runs entirely in the browser.
Frequently asked questions
What's the difference between contain and cover?
Contain shows the whole image with possible bars; cover fills the frame completely and crops some image areas to do so.
Is my video uploaded?
No. The adjustment runs entirely locally in the browser, without transmission to a server.
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