---
id: "lcc"
kind: "datatype"
status: "draft"
is_pii: false
categories: ["publishing"]
langs: ["common"]
quality: 100
url: "http://registry.apicrafter.io/datatype/lcc"
---

# Library of Congress Classification (LCC) number (`lcc`)

> **Draft.** Draft records have not been reviewed yet and may be incomplete or wrong; do not treat them as authoritative for legal or compliance decisions.

Class number or call number in the Library of Congress Classification, the subject classification of the US Library of Congress, which most research and academic libraries in the United States use to shelve books. It starts with one to three letters for the class and subclass, such as QA for mathematics or TK for electrical engineering, followed by a number with an optional decimal part. A call number adds Cutter numbers, such as .P98, and often a year. The regexp is adapted from the Wikidata format of property P1149 and requires a class number.

- Personal data (PII): no
- Categories: Publishing and print (publishing)
- Countries: global
- Languages: Common to most languages (common)
- Classification: categorical

## Detection

Regular expression (Python `re`):

```
^[A-Z]{1,3}\d+(?:\.\d+)?(?: *\.[A-Z]{0,3}\d+(?:[ -]\.?[A-Z]{0,3}\d+)?)?(?: *\d+[a-z]*)?$
```

## Examples

- `QA76` — Class number only
- `QA76.73.P98` — Class number with a Cutter number
- `TK5105.888` — Class number with a decimal part
- `QA` (invalid example) — Subclass letters without a number

## Mappings

- autotype: `lcc`
- wikidata: `P1149`

## Supported by tools

- `autotype`

## Translations

- ru: Индекс Классификации Библиотеки Конгресса (LCC): Классификационный индекс или шифр хранения по Классификации Библиотеки Конгресса США.

## Sources

- wikipedia: <https://en.wikipedia.org/wiki/Library_of_Congress_Classification>
- wikidata: <https://www.wikidata.org/wiki/Property:P1149>
- doc: <https://www.loc.gov/catdir/cpso/lcco/>
- other: <https://github.com/congy/AutoType/blob/master/data_release/lcc.txt>

## Quality

Score 100/100.

JSON: <http://registry.apicrafter.io/api/v1/datatypes/lcc.json> · Edit: <https://github.com/apicrafter/metacrafter-registry/edit/main/data/datatypes/any/objectids/lcc.yaml>