> For the complete documentation index, see [llms.txt](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/7.19.1/introduction/preferences/reasoners.md).

# Reasoners

### Available reasoners <a href="#applicationpreferences-availablereasoners" id="applicationpreferences-availablereasoners"></a>

Go to `File > Preferences > Snow Owl > Reasoners` to bring up the preference page.

Snow Owl includes the following reasoner:

| Reasoner                                         | Description                                                                                                                                                                           |
| ------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [ELK](http://code.google.com/p/elk-reasoner/ELK) | An ontology reasoner with the goal of supporting the OWL 2 EL profile. Remains the world's fastest SNOMED CT classifier and is Snow Owl's default. ELK supports numerical data types. |

![Reasoners Preferences Page](https://3959073837-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FRoMPum3fElXxzso90QiD%2Fuploads%2FbbevFyyMs0qfRRDuJPdQ%2Fpreferences_reasonsers.png?alt=media\&token=5c82ff62-6618-4e77-84a6-52b3c7f39b35)

The selected reasoner will be used for classifying SNOMED CT.&#x20;