Rectangle with round corners/SVG needed?

[Blighty]

(08-31-2017, 11:34 AM)BenjaminGer Wrote: Oh sorry. I am talking about inkscape. I attached the screenshots where you can see the size.

In Inkscape, the object has a fill and a stroke. The sizes you see are for the bounding box that encloses both fill and stroke.

Draw a 150x150 rectangle with fill but no stroke. It will behave as you are wanting.
Now add a stroke. 50% of the stroke will fall inside the rectangle, 50% outside. So the size of the bounding box increases to accommodate the stroke.

But the best place to ask Inkscape questions is here:
http://www.inkscapeforum.com