How to Edit Screenshots on Mac Computers?

By Amanda | Posted to Home > Howto, on November 2nd, 2021

Summary: This is a tutorial on how to edit screenshots on your Mac computers. Without any third-party software, the default app Preview can satisfy your needs.

How to edit screenshots on Mac

From time to time, people take a screenshot on Mac to extract information, save it in Photos, share it with friends or colleagues, provide a guide for their users, etc. With shortcuts and applications, it is easy to screenshot any content you want.

After grabbing a screenshot, people may need to edit the screenshot such as cropping, resizing, annotating, and so forth. In addition download a snipping tool for Mac, the built-in Preview app can also satisfy your basic needs. Next, we will show you how to use Preview to edit screenshots on Mac.

Get a screenshot into Preview

To edit a screenshot with Preview, you need to get it into Preview in the first place. There are different ways to import a screenshot to Preview. All of them are easy to follow.

Method 1. Find a saved screenshot on the desktop or in the Finder, double-click to open it. It will open in the Preview app by default. Or, control-click the screenshot and choose Open With > Preview.

Method 2. Launch the Preview app from Applications/Dock/Spotlight. From the top menu, click File > Open to choose a screenshot to edit, or click File > New From Clipboard to import the screenshot saved in your clipboard.

get a screenshot into Preview

How to edit a screenshot with Preview

Basic edits such as cropping, rotating, and resizing a screenshot are featured in the Preview app. In this part, we are going to dive into the detailed steps to edit a screenshot in Preview.

How to crop a screenshot

To crop any area of a screenshot on your Mac, you can follow the steps here.

From the menu bar in Preview, click the icon which looks like a pen nib in a circle, or click View > Show Markup Toolbar.

On the toolbar, click the first icon to select a part you want to crop. There are 4 patterns for you to choose from.

Click and drag on your Trackpad to select an area. Then release your finger.

A new icon pops up on the right corner of the toolbar, click it to crop the selected area.

select to crop an area of a screenshot

How to rotate or flip a screenshot

If you want to adjust the orientation of the screenshot, you can make it in Preview easily. From the navigation bar, there is a rotate icon, each time you click it, the screenshot will rotate 90 degrees to the left.

Alternatively, you can click Tools from the top menu bar. From the list, you can choose to rotate left, rotate right, flip vertical, and flip horizontal.

rotate or flip a screenshot

How to annotate on a screenshot

Preview includes various functions to annotate on a screenshot. It can help to clearly explain some content on the screenshot so that the reader can understand it better.

Add text

When you need to write on the screenshot, you can click the Text icon in the toolbar. It will add a text box to the image. Drag and drop it anywhere you want. Then, double-click the box to type content in the box.

Click the Aa icon to adjust the style and size of the written text on the screenshot, including font, size, color, bold, italic, underline, and alignment. What's more, you can adjust the thickness and color of the border, and the filling color of the whole box.

Insert shapes

Two ways to insert shapes on a screenshot. You can click the Shape icon in the toolbar, or click Tools from the top menu. Select line, arrow, oval, polygon, star, or speech buddle from the list. The Added shape will be surrounded by blue handles that let you resize it. If it has green handles, use them to alter the shape.

Highlight, loupe, and mask

To make an area of the screenshot stand out, you can use highlight, loupe, and mask in Preview.

Click any of them from Tools > Annotate, drag and drop it where you want. To resize it, use the blue handles.

annotate on a screenshot

How to resize a screenshot

In some cases, such as uploading an image for registration, the size of the image may be required. Or, you want to shrink screenshots so they don't take up as much visible area or on-disk space.

In Preview, click the Adjust Size icon from the toolbar, you can adjust the width, height, and resolution of a screenshot. Tick the checkbox next to Scale proportionally and Resample image to make the resized screenshot doesn't look stretched or smooshed.

resize screenshot

How to adjust the color of a screenshot

Just like you edit a photo on your iPhone, you can adjust the color of a screenshot on Mac as well, making it brighter or darker. Click Adjust color to open the dialogue. More options are provided.

Drag the axis on each dimension to the left and right to adjust the color of the screenshot. To adjust them automatically, click Auto Levels. To reset to the default, hit Reset all.

adjust the color of a screenshot

How to add a signature to a screenshot

Preview makes it convenient to sign on any screenshot without printing it out.

Click the Sign icon in the toolbar.

Choose to create a signature using a Trackpad, Camera, or iOS device.

Click Done when you finish signing.

Then click the Sign icon again, click the newly created signature from the list.

Drag the signature and put it anywhere on the screenshot.

sign on screenshot

Other edits you can make to a screenshot

Except for the basic edits mentioned above, there are some other tools in Preview. You can find them in the Toolbar or the top menu.

  1. Instant Alpha can remove the background from an image.
  2. Convert image files to a variety of file types by clicking File > Export.
  3. Zoom in and out a screenshot.
  4. Assign ColorSync profile to image.
  5. Check general info of the screenshot with Inspector.
  6. Rename the screenshot and change its location on your Mac.

FAQ about how to edit screenshots on Mac

Can I revert the edits on a screenshot in Preview?

Yes, you can use keyboard combination Command + Z to undo the change. Or click File > Revert to, here you can choose Last saved, Last opened, and Browse all versions.

How to customize the Toolbar in Preview?

From the top menu, click View > Customize Toolbar, a new window prompts. You can drag the items you like or the default set into the Toolbar. Then click the Done button.