The font size in the paint document refers to dots, not pixels. Change the font size in Photoshop to 30pt and they should be the same size.
The dot is 1/72 of an inch, and the pixel equivalent may depend on the DPI of your monitor. At 96 DPI, 30pt * 1in / 72pt * 96DPI (my res screen) is 40 pixels. To convert pixels to points, work backwards, so 30px * 1in / 96px * 72pt / 1in = 22.5pt.
So, change the layout text size to 22.5 and they should match.
source share