Notepad++ can count LOC (lines of code) of source files and give you the estimation of code size.
Press Ctrl+Shift+F shortcut to start "Find in files" dialog. Select "regular expression" search mode and start it.
Some regular expressions:
\S+\s*$-- all non-empty lines
^\s*$-- only empty (white-space) lines
^\s*class [^;]+$-- count class declarations (good metric with LOC ratio)