You can change image size (out of roblox) to 1:1 or if thats the size you can use “Fit” in imagelabel properties scaletype then click “Fit” option (dont know if this helps)
Unfortunately, there is no property for scaling the image relative to the background. You can obviously upload it with padding, but that isn’t very flexible. Instead, it is common to have a blank button (no image/text) with a smaller, centered ImageLabel for the icon.
Remove image/text from button
Add ImageLabel and set properties:
Image
BackgroundTransparency = 1
AnchorPoint = 0.5, 0.5
Position = {0.5, 0}, {0.5, 0}
Scale accordingly (e.g., Size = {0.8, 0}, {0.8, 0} covers 80% of the button)
For buttons without square dimensions, you can use the SizeConstraint property of the label to maintain the icon’s aspect ratio.
I would recommend you use a text button, set the text to “” then insert a image label inside of the text button and scale it to the size you want, and change the image.