Google goes for sure: in most cases when you type an expression it does both the calculation and the search. It omits the search only in very clear cases. Note that an equals sign can force calculation in some cases: two dozen dozen is search only, two dozen dozen = is both search and calculation.

Also note that the calculation is not done when it's dimensionally incompatible: 3 pounds to kilograms or 3 pounds to dollars are valid calculations, while 3 pounds to meters isn't. On the other hand, just like some handheld calculators, google doesn't care about some missing parenthesis or multiplication signs: 3 + 3) (7 + 5 is a well-formed calculation.