The Catalogue of Life offers releases that reflect different levels of coverage and quality: the Base and the eXtended Release. Throughout the year, these releases are updated in several versions: monthly and annual. Understanding the differences between these releases and their versions will help you navigate the Catalogue more effectively and choose the one best suited to your needs.

How to Quickly Decide What to Use?

• Need the most complete list across all taxonomic groups? -> Use the Catalogue of Life eXtended Release (XR).
• Need BIN numbers and other molecular identifiers? -> Use the Catalogue of Life eXtended Release (XR).
• Looking for the highest accuracy and long-term, expert-vetted information? -> Go with the Base Release.
• Want the most up-to-date information? -> Check out our monthly version (base or eXtended), always available on the website and in the Catalogue of Life ChecklistBank.
• Prefer stability for long-term analyses? -> Choose the Annual stable version (Base or eXtended) with ongoing support. A historical archive of all annual versions is available for all users.

For a more informed decision keep reading and also check the assembly page.

Base and eXtended Release

The Catalogue of Life Base Release (BR) is an assembly of non-overlapping, expert-curated global species checklists, organized according to the Catalogue’s management classification. The building process of this release ensures a higher level of quality, as most data sources are maintained and updated regularly by taxonomic experts. However, since many taxa still lack a vetted or up-to-date checklist, this approach leaves several gaps. To address this, the Catalogue of Life eXtended Release (XR) is built on top of the Base Release. This release is programmatically enhanced, integrating information from more than 60,000 overlapping taxonomic and nomenclatural sources including global, regional, national, and management datasets, as well as digitized literature. This process also enriches the existing names with information such as authorships, references, and vernacular names. It also adds molecular data, such as barcode index numbers or operational taxonomic units. Higher taxonomy is being added in selected groups with important gaps. Meanwhile, the information from the global data sources of the Catalogue of Life base release remains unmodified. This enhanced process is continuously evolving and undergoing quality control checks by COL editors and its community.

Annual and Monthly Versions

To keep the Catalogue up to date with the latest taxonomic views from our data providers, we publish monthly versions which are kept in ChecklistBank for at least one year. The accumulated monthly changes are reflected in the annual version. This version receives stable long-term support in COL’s data infrastructure. For this stable version, we take extra care to avoid introducing changes that could lead to errors. Annual versions of the catalogue have been published since 2000 (excluding 2001 and 2020).

The Catalogue history can be downloaded from our archives. Since 2021 we also keep a changelog of all releases.