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255  Cartographic Mathematical Data (R)

Record Type


Input Standards

Field (Full/Minimal)
Required if applicable/Required if applicable
1st Indicator  Undefined
blank character Undefined
2nd Indicator  Undefined
blank character Undefined
Subfields (R=Repeatable  NR=Nonrepeatable) Input Standards (Full/Minimal)
ǂa Statement of scale (NR) Mandatory/Mandatory
ǂb Statement of projection (NR) Required if applicable/Required if applicable
ǂc Statement of coordinates (NR) Required if applicable/Required if applicable
ǂd Statement of zone (NR) Required if applicable/Optional
ǂe Statement of equinox (NR) Required if applicable/Optional
ǂf Outer G-ring coordinate pairs (NR) Required if applicable/Optional
ǂg Exclusion G-ring coordinate pairs (NR) Required if applicable/Optional
ǂ6 Linkage (NR) System supplied/System supplied
ǂ7 Data provenance (R) Optional/Optional
ǂ8 Field link and sequence number (R) Optional/Optional


Mathematical data associated with cartographic material, including a statement of scale, statement of projection, and/or a statement of bounding coordinates. The coordinates can represent a bounding rectangle, the outline of the area covered, and/or the outline of a statement of bounding coordinates. For celestial charts, it may also contain a statement of zone, declination data, and/or right ascension data, and/or equinox.

Use field 034 for cartographic mathematical data in coded form corresponding to data recorded in field 255. Use field 500 for additional information about projection, coordinates, zone, and equinox. If you are entering a scale note for pre-RDA and pre-AACR2 cataloging, use field 507.

Use separate 255 fields for a multipart item with two different scales or a single item with components having two different scales. If a multipart item has three or more different scales, use one 255 field and enter Scales differ.

If this scale within a single item varies and the largest and smallest values are known, record the range. If the largest and smallest values are unknown, enter Scale varies.

If the scale cannot be determined or estimated, enter Scale not given.

If the cartographic content is not drawn to scale, enter Not drawn to scale.

See RDA 7.25 and Cartographic Materials, a Manual for Interpretation of AACR2, 2002 revision, for more information.

For information on punctuation, see the Punctuation section below.

1st Indicator

Undefined. The 1st indicator position is undefined and contains a blank.

blank character


2nd Indicator

Undefined. The 2nd indicator position is undefined and contains a blank.

blank character



ǂa Statement of scale

The entire scale statement including any equivalency statements. Vertical scales or vertical exaggeration statements for relief models or other three-dimensional items are also included in subfield ǂa.

255     Scale 1:24,000
255     Scale approximately 1:63,360
[Item indicates the scale is approximate]
255     Scale approximately 1:100,000
[Scale measured using a natural scale indicator]
255     Scale 1:253,440. 1 in. = 4 miles
[Verbal scale calculated into a representative fraction]
255     Scale 1:3,960. 7 in. equal 140 rods
255     Scale 1:250,000. Vertical scale 1:25,000
255     Scales differ
255     Scale varies
255     Scale not given
255     Not drawn to scale
ǂb Statement of projection

The entire projection statement.

255     Scale 1:2,500,000. 39.46 miles to the in. ; ǂb Albers conical equal-area projection
255     Scale 1:11,500,000 ; ǂb azimuthal equidistant projection ǂc (E 20°00'--E 80°00'/N 60°00'--N 10°00')
255     Scale 1:6,000,000. 94.7 miles to the in. ; ǂb Chamberlin trimetric projection
255     Scale 1:300,000 ; ǂb Gauss-Kruger conformal projection
255     Scale 1:63,360. 1 in. to the mile ; ǂb Lambert conformal conic projection ǂc (W 119°22ʹ30ʺ--W 117°52ʹ30ʺ/N 38°15ʹ00ʺ--N 36°00ʹ00ʺ)
255     Scale approximately 1:65,000,000 at the equator ; ǂb Mercator projection ǂc (W 180°--E 180°/N 80°--S 70°)
255     Scales differ ; ǂb polar stereographic projection
255     Scale 1:24,000 ; ǂb polyconic projection
255     Scale 1:35,000,000 ; ǂb Robinson projection, standard parallels 38°N and 38°S ǂc (W 180°--E 180°/N 90°--S 90°)
255     Scale approximately 1:4,750,000. 75 miles to the in. ; ǂb simple conic projection, with true parallels at 40° and 60°
ǂc Statement of coordinates

Coordinates are recorded in the order of westernmost longitude, easternmost longitude, northernmost latitude, and southernmost latitude. Record coordinates in the form hemisphere-degrees-minutes-seconds or, in other forms, such as decimal degrees. Enclose the coordinates in parentheses. The two longitude statements and the two latitude statements are each separated by two hyphens. The longitude is separated from the latitude by a slash.

255     Scale not given ǂc (W 150°--W 30°/N 70°--N 40°)
255     Scale 1:250,000 ; ǂb transverse Mercator projection. Everest spheroid ǂc (W 74°50ʹ--W 74°40ʹ/N 45°05ʹ--N 45°00ʹ)
255     Scale 1:7,500,000 ǂc (W 125°--W 65°/N 49°--N 25°)
255     Scale 1:126,720 ǂc (W 79°33ʹ--78°34ʹ/N 42°04ʹ--N 41°15ʹ)
255     Scale 1:90,000 ; ǂb Albers equal area projection ǂc (W 104°45ʹ00ʺ--W 103°17ʹ11ʺ/N 44°49ʹ23ʺ--N 43°16ʹ10ʺ)
255     Scale 1:100,000 ǂc (E 79.533265°--E 86.216635°/S 12.583377°--S 20.419532°)
[Coordinates presented as decimal degrees]
255     Scale 1:100,000 ǂc (E 079°32.5332ʹ--E 086°07.4478ʹ/S 012°35.5421ʹ--S 020°28.9704ʹ)
[Coordinates presented as degrees and decimal minutes]
255     Scale 1:100,000 ǂc (E 79°32ʹ35.575ʺ--E 86°07ʹ27.350ʺ/S 1°25ʹ36.895ʺ--S 20°28ʹ58.125ʺ)
[Coordinates presented as degrees, minutes, and decimal seconds]

If you enter the coordinates to define a center point rather than outside limits "bounding box", enter a single longitude and a single latitude (two sets of values instead of four):

255     Scale 1:75,000 ǂc (W 95°05ʹ/N 30°03ʹ)
255     Scale 1:25,000 ǂc (W 119.697222/N 034.420833)

Entering coordinates. Use the following characters to enter degrees, minutes, and seconds:

Symbol Action
degrees Use the degree symbol
minutes Use the miagkii znak
seconds Use the tverdyi znak
ǂd Statement of zone

The statement of zone for celestial charts.

255     Scales approximately 3 cm per degree ǂd (Zones -18° to -3°, -31° to -46°, -44° to 59°, -57° to -72°, -69° to -84° ; ǂe equinox 1875)
255     Scale not given ǂd (Right ascension 0 hr. to 24 hr./Declination +90° to -90°)
ǂe Statement of equinox

The statement of equinox or epoch.

255     Scale approximately 60 mm per 1° ǂd (Zones +90° to +87°, +87° to +81°, +81° to 75° ...-27° to -33° ; ǂe equinox 1950, epoch 1949-1958)
ǂf Outer G-ring coordinate pairs

Coordinate pairs that identify the closed nonintersecting boundary of the area covered.

ǂg Exclusion G-ring coordinate pairs

Coordinate pairs that identify the closed nonintersecting boundary of the area contained within the excluded G-polygon outer ring.

ǂ6 Linkage

Data that link fields when non-Latin script is entered. This subfield is system supplied and does not appear in OCLC online displays. Do not manually add subfield ǂ6. For more information about subfield ǂ6, see Control Subfields.

ǂ7 Data provenance

For information about subfield ǂ7, see the Data Provenance Subfields section of Control Subfields.

ǂ8 Field link and sequence number

For information about subfield ǂ8, see Control Subfields.


For records containing ISBD punctuation, follow these instructions:

  • Omit any punctuation between the word Scale (or its equivalents in other languages) and the representative fraction
  • Precede any additional scale information following the representative fraction by a period-space
  • Precede subfield ǂb by a space-semicolon-space
  • Enclose the text within any single or consecutive occurrences of subfields ǂc, ǂd, and/or ǂe within one set of parentheses
  • Separate two sets of longitude and latitude within a statement of coordinates by a slash
  • Separate each longitude or latitude from its counterpart within a statement of coordinates by two hyphens, not preceded or followed by a space
  • Enclose any text within brackets as required by cataloging instructions
  • Include incidental punctuation needed within any subfields, e.g., commas, periods (following abbreviations or initials), etc.
  • Optionally, add a terminal period at the end of the field unless the last subfield ends with an ellipsis or period (following an abbreviation or initial)
255     Scale 1:32,000,000 at equator ; ǂb Van der Grinten projection ǂc (W 180°--E 180°/N 85°--S 65°).

For records containing non-ISBD punctuation, see the cataloging instructions used to create the record.

For records containing minimal or no punctuation, include punctuation needed within any subfields. Otherwise, omit the punctuation outlined above.

255     Scale 1:32,000,000 at equator ǂb Van der Grinten projection ǂc W 180°--E 180°/N 85°--S 65°

For more information on punctuation, including OCLC policy, see section 2.8, Punctuation.


For indexing and searching information, see Searching WorldCat Indexes, field 255.


For more information, including content designator history, see MARC 21 Format for Bibliographic Data, field 255.

This page last revised: October 12, 2022