Help:Properties

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example of a simple statement consisting of one property-value pair

Properties, when paired with values, form a statement in Wikidata. A property describes the data value of a statement and can be thought of as a category of data, for example "color" for the data value "blue." Properties are also used in qualifiers.

Properties have their own pages on Wikidata and are connected to items, resulting in a linked data structure.

Understanding properties

Properties vs. items

Properties are similar to items in a couple of ways. Like items, each property has a label, a description, and even an alias or aliases that can be added in multiple languages.

P106 for English, French, and Polish
Label Description Alias
occupation occupation of a person profession; job; work; career
profession métier ou occupation d'une personne métier; occupation
zawód polsko-francuska uczona, fizyk, noblistka (none yet added)

However, properties do not have a section on their pages for adding statements or sitelinks. Instead, a property has what is known as a data type.

Like items, properties also have a unique identifier. While items begin with a Q prefix and are found in the main namespace of Wikidata, properties have a P prefix and are stored in the property namespace.

Finding properties

Properties can be suggested at respective classes using properties for this type (P1963). E.g. organization (Q43229) will list all properties relevant to any organization.

See Help:Properties/Statistics for additional summaries of existing properties.

Lists updated by a bot

Manually updated lists

Template:

Creating a new property

Before a new property is created, it has to be discussed and documented at Wikidata:Property proposal first. When after some time there are some supporters, but no or very few opponents, the property is created by a property creator or an administrator (see List of property creators). After creation, relevant documentation is moved to the corresponding property's talk page, where usage of the property is further discussed.

When proposing properties, keep in mind that each property should be expected to be used at least 100 items; if a proposed property cannot be used this many times, it likely should not be added to Wikidata (of course, there are exceptions to this rule).

To propose a property, click here and choose a topic category. Click the blue button "Create request page" and then fill out the provided template with as much information as possible. Make sure to include a possible property name in English (this will be the label), a description, the data type, examples of the type of item that may bear the property, and an example of how the property would be used. Don't worry about getting everything right the first time; that's what the discussion process is for.

If you are interested in being involved at the property proposal level for a specific subject matter, consider joining or creating a WikiProject, a group of contributors who want to work together to improve a particular aspect of Wikidata. These groups often focus on how to best represent the data for a particular area of knowledge.

To request to be a property creator, visit Wikidata:Requests for permissions.

Editing a property

Property entities can be edited like item entities with labels, descriptions, aliases, and statements.

Property labels should be as unambiguous as possible so that it is clear to a user which property is the correct one to use when editing items and adding statements. Properties rarely refer to commonly known concepts but they are more constructs of the Wikidata with specific meanings.

Property descriptions are less relevant for disambiguation but they should provide enough information about the scope and context of the property so that users understand appropriate usage of the property without having to consult additional help.

Property aliases should include all alternative ways of referring to the property.

Example:

property: P161
label: cast member
description: actor performing live for a camera or audience
aliases: film starring; actor; actress; starring

Label, description, and aliases of a property are first discussed by the community during the property proposal process. Major changes to a property should be discussed on its talk page first.

Deleting a property

If you think a property should be removed from Wikidata (for example, if is a duplicate of another property in use), you will have to make a request for its deletion. To do so, follow the steps listed at Wikidata:Properties for deletion.

Using properties

Wikidata relies on consistency. For instance, all persons should have common properties whenever possible, whether they are politicians, artists or scientists, living or historical, fictional or not. If you are unsure whether the property you are using is most appropriate for the statement, consult the property's discussion page or ask on Wikidata:Project chat. An automatically generated list of properties currently supported by Wikidata can be found at here. Community-maintained lists can also be found at Wikidata:List of properties.

Property constraints

See Help:Property constraints.

Bidirectional relationships and hierarchies

Wikidata does not support automatic bidirectional links (phabricator:T51165), so some properties need to be added and maintained twice. If, for example, A is a child of B on A's item page, the relation B as the parent of A also needs to be maintained on B's item page.

In general, only simple hierarchical properties should be recorded as statements. For example, record properties like child (P40)father (P22) and/or mother (P25), but not properties like grandchild–grandparent, niece–aunt, niece–uncle, etc. Such additional relationships can be derived from the existing data.

Frequently used properties

Please see Help:Properties/Frequently used properties for guidelines and examples of using properties related to scientific taxonomies, administrative divisions, sources, Wikimedia Commons files, and more.

See also

For related Help pages, see:

  • Help:Statements, which explains what statements are and what rules they follow
  • Help:Qualifiers, which explains what qualifiers are and what rules they follow
  • Help:Items, which explains what items are and what rules they follow

For additional information and guidance, see:

  • Project chat, for discussing all and any aspects of Wikidata
  • Wikidata:Glossary, the glossary of terms used in this and other Help pages
  • Help:FAQ, frequently asked questions asked and answered by the Wikidata community
  • Help:Contents, the Help portal featuring all the documentation available for Wikidata