Get started with Taxonomy API


Use the power of Candid's Philanthropy Classification System (PCS) taxonomy with the Taxonomy GraphQL API.

  • Build dynamic filtering capabilities to help users find causes that matter most to them.
  • Harness Candid's up to date taxonomy to enable users to explore the nonprofit sector.
  • Use GraphQL to get exactly the data you need in one API call.
  • Combine with other Candid APIs to create a robust nonprofit data system.


Candid's Taxonomy API is built using GraphQL. GraphQL APIs work differently than REST APIs by allowing you to select the data returned by each query. For more information about working with GraphQL, please see the Overview of GraphQL guide.

PCS Taxonomy

The Philanthropy Classification System (PCS) is Candid's taxonomy, describing the activities of the philanthropic sector. Candid's PCS is based on the National Taxonomy of Exempt Entities (NTEE) and has been expanded over the last three decades to include the emerging work we have evidenced while capturing and indexing the work of the sector on a global scale.

PCS classifies philanthropy activities under five facets: Subject, Population, Organization Type, Transaction Type, and Support Strategy.

PCS Subject Codes

Subject codes describe the core activities and services of an organization, often referred to as cause area. Examples include elementary education or clean water supply.

PCS Population Codes

Population codes describe the population served or impacted by a nonprofit's work. Examples include girls or people with disabilities.

More information about the PCS can be found at

GeoNames Taxonomy

The GeoNames taxonomy can be used to identify geographic information.

GeoName IDs can be used as search parameters to filter the Grants and News APIs by geographic areas.

API Reference

Use Cases

  • For donation platforms:
    • Create front-end menus to help users identify nonprofits working in cause areas of interest
  • For funders:
    • Leverage taxonomy codes when generating grant opportunities
  • For nonprofits:
    • Define work using taxonomy codes to help find funders and donations

Using Taxonomy API with other Candid APIs

Taxonomy API can be combined with Candid's Essentials, Grants, and News APIs to create a robust nonprofit data system. Taxonomy API can be used to build an interactive front end experience for end users, allowing them to select the taxonomy code that best encapsulates what they are looking for. On the back end, the selected code can be passed into the Essentials, Grants, or News APIs to identify relevant organizations, grants, or news articles.

Translating NTEE codes to PCS codes

The nteeMinor query returns an object called pcsCrosswalk. This provides the PCS code values and names that correspond with the searched NTEE code (where an equivalent value is available). This can be used to easily update systems that utilize the NTEE taxonomy to take advantage of the freshness and specificity of the PCS taxonomy.

Other taxonomies

Taxonomy API also includes access to the following IRS taxonomies:

  • NTEE Major
  • NTEE Minor
  • Filing Type
  • Subsection Code
  • Foundation Type
  • MSA Code