img tag scaling on R3D Forum

[SD-[Inc]]

Been posting a few images using the img tag lately and noticed that when they display on my browser they always scale up. If I set my browser at 100% scaling I would expect an image to display in the same pixel resolution as the source (i.e. 4k - 3840x2160). But when I bring it up in my browser it displays at a much larger resolution and I need to scale the browser view down to about 67% so it displays correctly on my 4K display at 3840x2160. Using Chrome as browser. Just curious if there is some browser or Windows setting that causes this. It seems to only happen on images in the forums here. The rest of the internet seem fine. Displaying the source URL from inside the img tag in a separate browser tab displays correctly also.