With Vimeo’s crop and fit feature, you can scale down your video’s media to fit any layout and ratio within Vimeo Create.
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Web
You will find the scale bar in the Scene Inspector to the right of your video in the video editor. Click and drag the scale icon or manually input a value within the range of 90% and 600% to scale the media in your video.
If you scale down your media to the point where your image or video clip does not fit the whole screen, Vimeo will “fill” the visible background of the scene with a fill color that will default to the secondary color found in the selected color palette. You can change this color by scrolling down in the Scene Inspector and clicking the Fill color swatch, then selecting a new color from the palette. If you scale your media up so that it takes up the whole screen, the color picker will become disabled.
Note: If you change the color palette for your video after manually selecting a fill color, the secondary color of the new palette will override your selection and become the new background color.
Mobile
To scale down an image in a Create video using the iOS or Android app, follow these steps:
1. Open the video you'd like to edit and click Edit.
2. Tap the image from the scene reel that you'd like to resize. 
3. Pinch the image with your fingers to zoom in and out. If you scale down your media to the point where your image or video clip does not fit the whole screen, Vimeo will “fill” the visible background of the scene with a fill color that will default to the secondary color found in the selected color palette.
4. To change the fill color, tap the Fill icon from the menu at the bottom of the screen.
5. Select a new color from the palette, then click Done. 