What do you mean by "font size of a book"? I assume you mean the text or body copy in the book.

One of these will come in handy, let me assure you. :-)

(Scroll to the right to see typographically useful part.)

Make sure you measure the entire body of the letter, not just the cap or lowercase.

DTP-Typometer, 24,80 €.
http://www.typographie.de/verlagsverzeichnis/typografie/643-6.html

yes, I mean the font size of the text of the book

is there any way to do it for free?

Ricardo Cordoba, how do I use this? I mean, I suppose I have to print it, but with which settings?

also what do I measure exactly? capitals, lowercase, etc etc?

thanks

The scale that Ricardo linked to is a precise measuring device, there is very little chance you could print it out accurately enough to be useable, software and printer would combine to foil you. The idea is that you can measure the cap (with the E) or x-height (with the x), however since typefaces vary in the amount of body they use it is not precise for all typefaces so once you have the approximate point size you can recreate the settings for measure and leading (which the scale will measure accurately) and finesse your point size by trial and error. You can also do that for free (although it takes time), to do this you need to precisely identify the typeface in both cases.

Tim

I measured the height of the capital E and found it 2mm

what is the font size?

"what is the font size"

I think you are best off identifying the font first. What's the font?

Cheers!

Around 9 pt, I guess…

: )

. . .
Bert Vanderveen BNO

Ricardo Cordoba, how do I use this? I mean, I suppose I have to print it, but with which settings?

Hi. I'm sorry, maybe I should have explained that a bit. That kind of scale is usually printed on clear acetate, so that you can place it on top of the book page (or other printed piece) and compare the book's type with the letters printed on the scale, until you find the closest match.

You can still find these scales at good art supply stores -- I've seen them at A.I. Friedman. (In the old days, you could get them from your friendly neighborhood typesetting office.)