Title: contour length
Long Title: IUPAC Gold Book - contour length
DOI: 10.1351/goldbook.C01308
Status: current

Definition
The maximum end-to-end distance of a linear polymer chain. For a single-strand polymer molecule, this usually means the end-to-end distance of the chain extended to the all-transconformation. For chains with complex structure, only an approximate value of the contour length may be accessible. The sum of the lengths of all skeletal bonds of a single-strand polymer molecule is occasionally termed 'contour length'. This use of this term is discouraged.

Related Terms
- conformation: https://goldbook.iupac.org//terms/view/C01258
- linear polymer: https://goldbook.iupac.org//terms/view/L03556
- single-strand polymer: https://goldbook.iupac.org//terms/view/S05694
- trans: https://goldbook.iupac.org//terms/view/C01092

Source
- Purple Book, 1st ed., p. 50 (http://old.iupac.org/publications/books/author/metanomski.html)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01308/html
- json: https://goldbook.iupac.org/terms/view/C01308/json
- xml: https://goldbook.iupac.org/terms/view/C01308/xml

Citation: Citation: 'contour length' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C01308
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-01-14T00:51:27+00:00