You can crop images without actually changing the image files by masking the edges to get rid of unwanted parts or to change the outline of the image. If you don’t specify a shape for the mask, by default Keynote uses a rectangular mask, but you can use any shape available in Keynote, including a custom shape that you’ve created with the Draw tool, to mask the edges of your image.

To mask an image with a rectangle:

  1. Import the image you want to mask. See Importing Images Working with Images to learn about importing images.

  2. Select the image and then click the Mask button in the toolbar (or choose Format > Mask).

    A mask appears over the image, and some controls appear.

  3. To resize the image, drag the slider above the Edit Mask button.

  4. Refine the mask by doing any of the following:

    • To resize the mask, drag the selection handles on the mask shape. To constrain the mask’s proportions, hold down the Shift key as you drag.

    • To rotate the mask, hold down the Command key as you drag a corner selection handle on the mask.

  5. Drag the image to position the part you want to show, or move the mask by clicking its edge and dragging it.

  6. When you’re satisfied with the position and size of your image and the mask, do any of the following to finish:

    • Double-click the mask or the image.

    • Press Return.

    • Click outside the image.

    • Click Edit Mask.

  7. To resize or rotate the masked image, drag or Command-drag its selection handles.

  8. To change the size of the masked image, double-click the masked image, and then click Edit Mask.

    Repeat the steps above as needed.

  9. To unmask the image, click Unmask in the toolbar (or choose Format > Unmask).

To mask the image with a predrawn shape (for example, a circle or a star):

Select the image and choose Format > “Mask with Shape” > Shape.

Resize and align the image and the mask as for any masked image, described above.

To mask the image with a custom shape:

  1. Create the shape you want to use as a mask and drag it over the image you want to mask.

  2. Hold down the Shift key and click to select both the shape and the image, and then click Mask in the toolbar (or choose Format > “Mask with Selected Shape”).

  3. Resize and align the image and the mask as for any masked image, described above.

If you’ve masked a very large image file and you only need to use the smaller version in your presentation, you can have Keynote keep only the smaller copy of the image, thus reducing the overall size of your document. See Reducing Image File Sizes.

Was this page helpful? Send feedback.