Struct Domain 

pub struct Domain {
    pub id: String,
    pub display_name: Option<String>,
    pub description: Option<String>,
    pub ids: Option<HierarchyIds>,
    pub display_name_alternatives: Option<Vec<String>>,
    pub fields: Option<Vec<HierarchyEntity>>,
    pub siblings: Option<Vec<HierarchyEntity>>,
    pub works_count: Option<i64>,
    pub cited_by_count: Option<i64>,
    pub works_api_url: Option<String>,
    pub updated_date: Option<String>,
    pub created_date: Option<String>,
}

A top-level research domain in OpenAlex’s topic hierarchy.

Domains are the broadest level: domain > field > subfield > topic. There are 4 domains: Life Sciences, Social Sciences, Physical Sciences, and Health Sciences.

Example

{
  "id": "https://openalex.org/domains/3",
  "display_name": "Physical Sciences",
  "description": "branch of natural science that studies non-living systems",
  "fields": [{"id": "https://openalex.org/fields/17", "display_name": "Computer Science"}, ...],
  "works_count": 134263529
}

ID formats

Domains use numeric IDs: 1 (Life Sciences), 2 (Social Sciences), 3 (Physical Sciences), 4 (Health Sciences).

Note

Domains do not support autocomplete (/autocomplete/domains returns 404).

Fields

id: String

OpenAlex ID URI (e.g. "https://openalex.org/domains/3").

display_name: Option<String>

Human-readable domain name (e.g. "Physical Sciences").

description: Option<String>

Brief description of the domain’s scope.

ids: Option<HierarchyIds>

External identifiers (OpenAlex, Wikidata, Wikipedia).

display_name_alternatives: Option<Vec<String>>

Alternative names or name variants.

fields: Option<Vec<HierarchyEntity>>

Academic fields within this domain.

siblings: Option<Vec<HierarchyEntity>>

Other domains at the same level in the hierarchy.

works_count: Option<i64>

Total number of works in this domain.

cited_by_count: Option<i64>

Total number of citations received by works in this domain.

works_api_url: Option<String>

API URL to retrieve works in this domain.

updated_date: Option<String>

ISO 8601 timestamp of the last update to this record.

created_date: Option<String>

ISO 8601 date when this record was first created.

Trait Implementations

impl Clone for Domain

fn clone(&self) -> Domain

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Domain

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Domain

fn deserialize<__D>( __deserializer: __D, ) -> Result<Domain, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl From<Domain> for DomainSummary

fn from(d: Domain) -> Self

Converts to this type from the input type.

impl Serialize for Domain

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.