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This page in a nutshell:

Properties describe the data value of a statement
Properties, like items, have their own unique pages on Wikidata
Properties, unlike items, must first be approved by the Wikidata community before being created

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

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, when paired with values, form a statement in Wikidata. Properties are also used in qualifiers.

Wikidata currently has 12,286 properties.

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

Understanding properties

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. Properties also have statements that help to more completely describe the property, including constraints on how the property can be used.

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	zawód osoby, zobacz także "dziedzina"	(none yet added)

However, properties do not have a section on their pages for sitelinks to other Wikimedia projects, and they also do not have external identifiers.

Each property has a data type which defines the kind of values allowed in statements with that property.

Properties aim to relate one type of entity with another type. The type of item a property should be used on is called its domain (Q112036279) and can be enforced using a subject type constraint (Q21503250). If the data type of an item is an Item, than the type of item that should be the value of the property is called is range (Q112036270) and can be enforced using a value-type constraint (Q21510865). If the data type is not an Item, the type of a value a property has can be specified with class of non-item property value (P10726).

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 Statistics for additional summaries of existing properties.

Search

Search

Several external tools exist to list properties, for instance:

Wikidata Property Explorer

Deleting properties

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 portal.

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.

Property misuse

Every Wikidata property is intended for a specific purpose. When a Wikidata property is used in a way that goes against the consensus of how the property is meant to be used, we speak of property misuse. Wikidata attempts to combat property misuse with property constraints and entity schemas. If a property is misused because there doesn't exist any good alternative property, a new property may be proposed.

Frequently used properties

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

Help:Frequently used properties, for help with using specific properties
- Help:Basic membership properties, detailed explanation of three important properties: instance of (P31), subclass of (P279) and part of (P361)
Wikidata:List of properties, community-maintained lists of Wikidata properties - Special:AllPages/Property:, a special page showing all properties
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
Wikidata:Property proposal, to discuss new properties before they are created - Wikidata:Properties for deletion to nominate properties for deletion
Wikidata:Property creators, for users granted the technical ability to create properties
Wikidata:WikiProjects, a list of users who work together to improve representation and coverage of a specific topic or domain
Wikidata:Relation between properties in RDF and in Wikidata
Wikidata:WikiProject Ontology
Wikidata:Identifiers for identifiers in Wikidata in general and identifier properties in particular
Wikidata:WikiProject Properties
MediaWiki:Wikibase-SortedProperties controls the order in which properties are presented on an item

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

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-== Creating properties == <!--T:46-->
-</translate>
-{{main|Wikidata:Property creation}}
-<translate>
-<!--T:12-->
-Before a new property is created, it has to be discussed and documented at {{ll|Wikidata:Property proposal|Wikidata:Property proposal}} first. When after some time there are some supporters, but no or very few opponents, the property is created by a {{ll|Wikidata:Property creators|property creator}} or an {{ll|Wikidata:Administrators|administrator}} (see [[Special:ListUsers/propertycreator|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.
-<!--T:13-->
-When proposing properties, keep in mind that each property should be expected to be used by 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).
-<!--T:14-->
-To propose a property, click {{ll|Wikidata:Property proposal|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.
-<!--T:15-->
-If you are interested in being involved at the property proposal level for a specific subject matter, consider joining or creating a {{ll|Wikidata:WikiProjects|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.
-<!--T:16-->
-For more information on the property creator role, see [[<tvar name="1">Special:MyLanguage/Wikidata:Property creators#Requesting this right</tvar>|Wikidata:Property creators#Requesting this right]]. To request the userright, visit <tvar name="2">[[Wikidata:Requests for permissions/Other rights#Property creator]]</tvar>.
 ==Deleting properties== <!--T:23-->