Directory (NR)
MARC 21 Bibliographic - Concise
2008
This is an ARCHIVED VERSION of the
2008 electronic edition of the MARC 21 Concise
Formats. Please see loc.gov/marc/concise/
for the most up-to-date version of the electronic MARC 21
Concise Formats.
Computer-generated index to the location of the variable
control and data fields within a record. The Directory
immediately follows the Leader at character position 24 and
consists of a series of fixed-length (12 character positions)
entries that give the tag, length, and starting character
position of each variable field.
Character Positions
00-02 - Tag
Three ASCII numeric or ASCII alphabetic characters (upper
case or lower case, but not both) that identify an
associated variable field.
03-06 - Field length
Four ASCII numeric characters that specify the length of
the variable field, including indicators, subfield codes,
data, and the field terminator. A Field length number of
less than four digits is right justified and unused
positions contain zeros.
07-11 - Starting character position
Five ASCII numeric characters that specify the starting
character position of the variable field relative to the
Base address of data (Leader/12-16) of the record. A
Starting character position number of less than five digits
is right justified and unused positions contain zeros.