> For the complete documentation index, see [llms.txt](https://docs.os.uk/os-downloads/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.os.uk/os-downloads/products/areas-and-zones-portfolio/code-point/code-point-technical-specification.md).

# Code-Point Technical Specification

This technical specification provides detailed technical information about Code-Point. It is targeted at technical users and software developers.

Code-Point is a dataset that contains postcode units for Great Britain and Northern Ireland, each having a notional geographical location. Postcodes are an alphanumeric abbreviated form of an address. Postcode units are unique references and identify an average of 15 addresses. In some cases, where an address receives a substantial amount of mail, a postcode will apply to only one address and is defined as a large-user postcode. The maximum number of addresses in a postcode is 100.

## Index <a href="#id-2.-product-structure" id="id-2.-product-structure"></a>

This technical specification includes the following sections:

* [Product structure](/os-downloads/products/areas-and-zones-portfolio/code-point/code-point-technical-specification/product-structure.md)
* [Supply formats](/os-downloads/products/areas-and-zones-portfolio/code-point/code-point-technical-specification/supply-formats.md)


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