I am working on a landing page design. The artboard size I am working with is '1920x1080' in 'Adobe xD' on a mac. On viewing it at 100% the design does not fit into my screen. Also a major problem I am facing is with developer, he is saying if he is using the font sizes I shared with him the design odd as the font sizes in my version and his while viewing on the browser don't match.
It depends what units the developer is using for the font sizes.
The font size in Xd is in pixels. If instead of px he is using pt, that's way different. 16px font size amounts to 12pt. So if he is looking at the number 16, and making the font size 16pt, that is about 21 pixels, thus making it bigger than your design.
P.S. If you can share the prototype or the file, vs what the coded website looks like, that would be helpful in identifying the issue.