How to expand canvas with equal boarder on all sides?

[Lizard Cobra]

I want to expand my canvas so that every side has the same boarder width? I just want to add a white boarder to each of the four sides.

I tried doing Document-> Resize Canvas, but this is not working. I have selected the anchor point to be in the center. However, when the canvas is resized, for some reason it is not expanding equally on the opposite sides. If I click the lock to constrain the ratio, the left and right boarders appear to be close to equal. But the canvas is only expanded upwards, leaving all of the white boarder on the top only, with no boarder at all on the bottom. It's acting as if I had instead selected the bottom center anchor checkbox (which I did not). If I unlock, to unconstrain the ratio, the top and bottom boarder appear to be close. But it is putting a far wider boarder on the right than on the left. The width of the right boarder for some reason is around 3 times as wide as the left boarder.

[firstdefence]

See this post that asks the same question

 

[firstdefence]

You could also try the two squares technique.

1. So you have an image with no border but you want a 2cm border all around.
2. Create a square shape 2cm er square lol!
3. and place the bottom right bounding box node on the top left bounding box node of the image
   
4. Duplicate Press CMD (⌘) + J on Mac, Ctrl + J On Windows) that square and place it in the same manner on the bottom left node of the image
   
5. Now go to Document > Unclip canvas and you will end up with this
   
6. Either delete of hide the squares.

Result

[v_kyr]

51 minutes ago, Lizard Cobra said:

I want to expand my canvas so that every side has the same boarder width? I just want to add a white boarder to each of the four sides.

I tried doing Document-> Resize Canvas, but this is not working. I have selected the anchor point to be in the center. However, when the canvas is resized, for some reason it is not expanding equally on the opposite sides.

Do as you did before (unlock & select and select the anchor point to be in the center), but this time add to both fields the same amount of pixels for your border size (xxx + nn px). - For example, size = 857 + 40 px, 643 + 40 px   ==>  897 px, 683 px...

... just add to the values in both fields the same amount of pixel, by typing in "xxx + xx" into both!

 

[Lizard Cobra]

@firstdefence That ended up working, thank you!

In case anyone else finds themselves in this situation, I'll elaborate:

Actually, when I followed the steps in your second post, it didn't work the first time. It still only added a boarder to the top, and no white border was added to the bottom. Though I noticed that when I clicked "Unclip canvas", it made a few cm at the bottom of my document visible. I don't know how that bottom strip got hidden in the first place.  But it was apparently included in my canvas, and for some reason was just being hidden in the display? I'm not sure exactly.

Anyways, undid all actions to start from the beginning. I selected Document > Unclip canvas, then expanded the document using the steps that I described in my original post. It then worked as expected.

I also tried your method, but adding the step Document > Unclip canvas before starting your steps. Doing it that way, your solution also worked.