how to increase border on a jpeg

1. That's something you would have to do in a graphics program, not Preview
2. Again something you would do in a graphics program. FWIW, jpegs do not support transparency.

If you don't want to invest in a graphics app you could use the free GIMP.

https://www.gimp.org/

Using Preview, you can take a copy of an existing image (any image) or a screenshot of anything.

Resize the image to the dimensions you want.

Select everything in the image (Preview -> Edit -> Select all), and use Preview -> Edit -> Cut to eliminate the original stuff you do not want.

You now have a blank canvas the size you want.

Have Preview open your desired image, and Preview -> Edit -> Select all.

Preview -> Edit -> Copy

Now paste your desired image into your blank canvas.

You should be able to drag the pasted image around to center it the way you want.

If you have created your blank canvas larger than originally desired, you can select what you want to keep, and crop the image to the desired size.

JohnMo222 wrote:

Two questions about Preview:

1 How can I increase the border around a jpeg or png image (i.e., create more whitespace)?

2 How can I convert whitespace border to transparency?

Have these questions already been dealt with? I searched but can't find anything. Many thanks.

Preview is not a photo editor per say, it has limited functionality.

There are many ways to accomplish your goals...and could be done with Preview.app, once you understand the basics of photo manipulation.

one ex. https://helpx.adobe.com/photoshop/how-to/add-border-frame-around-photo.html

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