A Guide on How to Remove Image Background in Preview

As a Mac user, if you are preparing to create an image with a transparent background or need to change the background of a current image, the system-installed Preview tool may be your first choice.

The primary function of this software is to help you preview images or PDF files stored on your computer. However, it also includes some basic image repair and editing features, including the background removal feature we will discuss today. Preview provides four functions that can achieve this operation.

This guide is specifically designed to teach you how to remove background in Preview. We will provide detailed step-by-step instructions for each of the four methods, and additionally, we will introduce a more intelligent background remover.

Part 1. How to Remove Background in Preview on Mac

Let's jump right into how to remove the background from a picture in Preview.

This section will show you the step-by-step process using four different methods.

Use Instant Alpha

Instant Alpha is suitable for images with a solid-color background and a high contrast between the background and the subject. In other words, it can be used for basic background removal.

Here is how to remove background in Preview Mac with Instant Alpha.

Step 1. Locate the file you want to edit, right-click it, select Open With, and choose Preview.

Step 2. On the toolbar, click the Show Markup Toolbar button to reveal the editing menu.

Step 3. Find the Instant Alpha icon on the left side of the toolbar and click it.

Step 4. Click and drag your cursor over the background area. The red highlight shows what will be selected for removal.

Step 5. Release your mouse to confirm the selection, then press Delete to remove it.

Step 6. When satisfied with the result, press Cmd + S to save the edited image.

Use the Rectangular and Elliptical Selection

The Mac Instant Alpha feature can only automatically remove the background it detects, and the background and subject colors cannot be too similar.

Now let's move on to the advanced level, where you manually select the object you want to keep. Preview's Rectangular and Elliptical Selection allows you to crop the part you want to keep in an oval or rectangle, and then delete the original background. Finally, paste the cropped subject back in.

Here is how to use Mac Preview to remove background with Rectangular and Elliptical Selection.

Step 1. Right-click the file, choose Open With, and select Preview.

Step 2. Click the Show Markup Toolbar button on the right side of the toolbar.

Step 3. Click the Selection Tools button on the left, then pick Elliptical Selection or Rectangular Selection from the drop-down menu.

Step 4. Drag to highlight the object you want to keep, then press Cmd + X to cut it out.

Step 5. Choose Cmd + A to select the remaining background. Next, press Delete.

Step 6. Choose Cmd + V to paste the object back into place.

Step 7. When everything looks right, press Cmd + S to save the changes.

Use the Lasso Selection

Now we come to a more complicated situation: what if the subject color you want to keep is too similar to the background color? In this case, you may need an advanced tool—the Lasso Selection. With it enabled, you can manually draw lines to precisely outline the part you want to keep, and then delete the rest of the background.

Here is how to remove background in Preview with Lasso Selection.

Step 1. Double-click the file or open it in Preview to start editing.

Step 2. Click the Show Markup Toolbar button on the left side of the toolbar.

Step 3. Click Selection Tools and select Lasso Selection from the menu.

Step 4. Click and drag to draw freely around the object or section you want to remove.

Step 5. Press Delete to remove the outlined area from the image.

Use the Smart Lasso

A new problem may arise: what if the outline of the subject in the image is too complex, making manual selection take a long time?

No problem, there is another advanced feature waiting for you to try: Smart Lasso.

Smart Lasso allows you to enjoy semi-automatic selection. You only need to roughly trace the outline of the subject, and Preview will automatically detect the color and contrast to attach to the outline. This greatly speeds up the processing task.

Here is how to apply Smart Lasso.

Step 1. In the toolbar, click the Markup button to reveal the editing tools.

Step 2. Open the Selection Tool menu and choose Smart Lasso from the options on the left.

Step 3. Trace around your subject, making sure the start and end points meet to complete the outline.

Step 4. Press Delete to remove the background, or copy the selected object to use elsewhere.

Part 2. Best Alternative to Preview to Remove Image Background for Free

Although using Preview to remove image backgrounds is simple and convenient to launch, there are issues that cannot be ignored: the edges of the removed background are not precise enough, often resulting in small areas being either added or missing.

If you want to achieve more perfect results, we recommend using the smarter online tool FVC Free Background Remover.

This platform only requires you to upload your photo—no clicking, no manual selection of the area—and within seconds, your image will have its background successfully removed. The usage steps are extremely simple, and the output images are watermark-free.

Here is how to remove image background with FVC Free Background Remover.

Step 1. Open your browser and go to FVC Free Background Remover. Click Upload Image to select the photo you wish to edit.

Step 2. The tool will automatically remove the background, making it transparent. Review the result and use the editing options to refine it if needed.

Step 3. When you’re satisfied, click Download to save your finished image to your device.

Part 3. FAQs of Removing Background in Preview

Conclusion

This article provides four methods for removing backgrounds in Preview, including one for automatically removing the selected background, two for manually selecting and removing backgrounds, and one for semi-automatically removing backgrounds. The operations are simple, but the results may not be perfect.
If you need a smarter and more efficient method, we recommend trying FVC Free Background Remover. Simply upload the image, and it will handle the rest.