How To Edit Images on a Mac

You don't need to be an expert in PhotoShop to do some basic image editing on Mac computers. Preview allows you to easily crop images, as well as adjust their size and resolution, all within one program. The application comes pre-installed on all OS X computers, so no downloads or installation are necessary.

This article will teach you how to use Preview to edit and annotate your images.

Crop Images Using Preview

To crop an image or photo, simply open the file and then select the area of the image you'd like to keep. Once selected, you can either press the Command + K keys, or navigate to the toolbar and click Tools > Crop:

Edit Image Size Using Preview

To adjust the size and resolution of your image, head to the Tools option and then click Adjust size:

Here, you can adjust the height and weight of your image by entering in your specific image specs relative to pixel size, percentage, inches, or centimeters. By default, the system adjust the image proportionally, but you can change this by either unchecking the Scale option, or by clicking the lock button next to the drop down menu, and entering in your values manually:

Alternatively, you can also choose from one of Preview's pre-determined images sizes, such as 640x480 or 800x600.

Annotate Images Using Preview

In addition to image sizing options, the toolbar also allows you to edit your image by adding text, shapes, and custom drawings. To access the toolbar (if it is not already shown), click on the small toolbox icon next to the Search field:

Using these tools, you can insert different shapes over your image, and customize them with different colors and borders. Also available is the option to draw freehand over your image (using the pencil icon), signature and text insertions, as well as standard image editing tools to adjust the lighting and exposure.

Insert Text in Preview

To add text to your image, click on the T icon shown within a small rectangle. A small text field will appear on your image. Click inside the box to edit the text, and adjust the colors and font size by clicking on the A on the right-hand side of the toolbar.

Once your text is inserted, you can place it anywhere via a simple drag and drop:

All edits are automatically saved to your file, but you can also save edits at anytime by hitting Control + S.

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