Cast-off Calculator

Formula for estimating the length of a book manuscript based on a castoff. The numbers in this example come from the manuscript excerpted in figure A.5 and are reflected in the typeset page in figure A.6.

Necessary calculation to determine the final, typeset length of a printed book. The estimator begins with the raw manuscript and calculates how many printed pages the manuscript copy will run based on the following:

  1. Type size: Size of letters, measured in points
  2. Typeface: Style of type (e.g., Stempel Garamond, Adobe Caslon, etc.). Also now referred to as “font” in desktop publishing industry
  3. Line measure: Length of typeset line, measured in picas
  4. Page fill: Number of lines per page

(These four items are derived from the book design.)

Original Manuscript
Average characters per line (over ten lines)
Average lines per page (over ten pages)
Number of manuscript pages
Typeset page
Body text face
Picas per line
Number of lines per page