Annotate an image in Preview on Mac
You can use the editing tools in the Markup toolbar to mark up an image file, providing feedback or pointing out something you want to remember.
If the image is on a page in a PDF file and you want to comment on only the image, you can extract the image as a separate image file. See Extract a PDF page as an image for instructions.
If you only want to comment on part of an image that you’ve opened in Preview, you can select part of it, choose Edit > Copy to copy just that part, then choose File > New from Clipboard to create a new file. You can also crop the image to remove areas that you don’t want.
Note: If you annotate an image file, you can’t edit, move, or delete the annotations after you save the image. If you think you’ll need to change annotations later, you can convert the image file to a PDF file, then add annotations to the PDF.
Go to the Preview app
on your Mac.Open the image you want to annotate.
Click
(if the Markup toolbar isn’t showing).Use the tools in the toolbar to mark up the image.
Tool
Description
Rectangular Selection
Select a rectangular area in an image to copy or delete.
Elliptical Selection
Select a circular or elliptical area in an image to copy or delete.
Lasso Selection
Select an irregular area in an image to copy or delete.
Smart Lasso
Select an area you outline in an image to copy or delete.
Instant Alpha
Remove the background from an image.
Sketch
Sketch a shape using a single stroke.
If your drawing is recognized as a standard shape, it’s replaced by that shape; to use your drawing instead, choose it from the palette that’s shown.
Draw
Draw a shape using a single stroke. Press your finger more firmly on the trackpad to draw with a heavier, darker line.
This tool appears only on computers with a Force Touch trackpad.
Shapes
Click a shape, then drag it where you want. To resize the shape, use the blue handles. If it has green handles, use them to alter the shape.
You can add a highlight shape or zoom lens using these tools:
Highlight
: Drag the highlight where you want. To resize it, use the blue handles.Zoom
See Rotate and modify shapes added to a PDF for more options.
Text
Type your text, then drag the text box where you want.
Sign
If signatures are listed, click one, then drag it where you want. To resize it, use the blue handles.
To create a new signature, see Fill out and sign PDF forms in Preview on Mac.
Adjust color
Change values for an image’s exposure, contrast, saturation, tint, and more.
To have the values automatically adjusted, click Auto Levels. To return to the original values, click Reset All.
Adjust size
Change an image’s size and resolution.
Shape Style
Change the thickness and type of lines used in a shape, or add a shadow.
Border Color
Change the color of the lines used in a shape.
Fill Color
Change the color that’s used inside a shape.
Text Style
Change the font or the font style and color.
Rotate Left
or Rotate Right 
Click
to rotate an item to the left. Continue clicking to keep rotating.To rotate an item to the right, press and hold the Option key, then click
until you’re done rotating the item.Crop
Hide part of an image. Click and drag over the image so that a frame appears. Drag the corner handles until just the area you want to keep is shown within the frame’s border. You can also drag the frame to reposition it. When you’re ready, click
.Image description
Enter, view, or edit a description of an image. (The tool is highlighted when an image has a description.)
Image descriptions can be read by screen readers and are useful for anyone who has difficulty seeing images online. For example, if you use VoiceOver, the built-in screen reader on Mac, you can press the VoiceOver command VO-Shift-L to hear a description of the image in the VoiceOver cursor.
