US Census Bureau

US Census Bureau ACS API

American Community Survey datasets (1-Year, Supplemental, 5-Year)

Documentation GitHub OpenAPI

Operations 5

GET /{vintage}/acs/acs5 Get ACS 5-Year Detailed Tables #

GET /{vintage}/acs/acs5/subject Get ACS 5-Year Subject Tables #

GET /{vintage}/acs/acs5/profile Get ACS 5-Year Data Profiles #

GET /{vintage}/acs/acs1 Get ACS 1-Year Detailed Tables #

GET /{vintage}/acs/acs1/supplemental Get ACS 1-Year Supplemental Estimates #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Census Data ACS API
  description: 'The Census Data API provides programmatic access to over 1,700 datasets

    published by the U.S. Census Bureau including the American Community Survey

    (ACS), Decennial Census, Economic Census, Population Estimates, County

    Business Patterns, Nonemployer Statistics, Annual Business Survey, and

    Household Pulse Survey.


    All endpoints follow the pattern `/data/{vintage}/{dataset-path}` and return

    a two-dimensional JSON array where the first row is the variable header and

    each subsequent row is a record. Every query requires a free `key` query

    parameter obtained from https://api.census.gov/data/key_signup.html.


    Responses are released into the public domain under Creative Commons Zero

    (CC0). Applications must display: "This product uses the Census Bureau Data

    API but is not endorsed or certified by the Census Bureau."

    '
  version: '2026-05-25'
  contact:
    name: Census Bureau Developer Support
    email: cnmp.developers.list@census.gov
    url: https://www.census.gov/data/developers/about.html
  license:
    name: Creative Commons Zero 1.0 (Public Domain)
    url: https://creativecommons.org/publicdomain/zero/1.0/
  termsOfService: https://www.census.gov/data/developers/about/terms-of-service.html
servers:
- url: https://api.census.gov/data
  description: Census Data API production base
security:
- ApiKeyQuery: []
tags:
- name: ACS
  description: American Community Survey datasets (1-Year, Supplemental, 5-Year)
paths:
  /{vintage}/acs/acs5:
    get:
      summary: Get ACS 5-Year Detailed Tables
      description: 'Query American Community Survey 5-Year Estimates detailed tables for a

        given vintage (2009 through the latest release year). Returns variables

        for the specified geographies.

        '
      operationId: getAcs5
      tags:
      - ACS
      parameters:
      - $ref: '#/components/parameters/VintagePath'
      - $ref: '#/components/parameters/GetParam'
      - $ref: '#/components/parameters/ForParam'
      - $ref: '#/components/parameters/InParam'
      - $ref: '#/components/parameters/UcgidParam'
      - $ref: '#/components/parameters/KeyParam'
      responses:
        '200':
          description: ACS 5-Year detailed tables result set (header row + value rows)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DataMatrix'
        '400':
          $ref: '#/components/responses/BadRequest'
        '404':
          $ref: '#/components/responses/NotFound'
  /{vintage}/acs/acs5/subject:
    get:
      summary: Get ACS 5-Year Subject Tables
      description: Query ACS 5-Year Estimates Subject Tables (S-prefixed table IDs).
      operationId: getAcs5Subject
      tags:
      - ACS
      parameters:
      - $ref: '#/components/parameters/VintagePath'
      - $ref: '#/components/parameters/GetParam'
      - $ref: '#/components/parameters/ForParam'
      - $ref: '#/components/parameters/InParam'
      - $ref: '#/components/parameters/KeyParam'
      responses:
        '200':
          description: ACS subject tables result set
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DataMatrix'
  /{vintage}/acs/acs5/profile:
    get:
      summary: Get ACS 5-Year Data Profiles
      description: Query ACS 5-Year Estimates Data Profiles (DP-prefixed table IDs).
      operationId: getAcs5Profile
      tags:
      - ACS
      parameters:
      - $ref: '#/components/parameters/VintagePath'
      - $ref: '#/components/parameters/GetParam'
      - $ref: '#/components/parameters/ForParam'
      - $ref: '#/components/parameters/InParam'
      - $ref: '#/components/parameters/KeyParam'
      responses:
        '200':
          description: ACS data profiles result set
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DataMatrix'
  /{vintage}/acs/acs1:
    get:
      summary: Get ACS 1-Year Detailed Tables
      description: Query ACS 1-Year Estimates for geographies with 65,000+ population.
      operationId: getAcs1
      tags:
      - ACS
      parameters:
      - $ref: '#/components/parameters/VintagePath'
      - $ref: '#/components/parameters/GetParam'
      - $ref: '#/components/parameters/ForParam'
      - $ref: '#/components/parameters/InParam'
      - $ref: '#/components/parameters/KeyParam'
      responses:
        '200':
          description: ACS 1-Year detailed tables result set
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DataMatrix'
  /{vintage}/acs/acs1/supplemental:
    get:
      summary: Get ACS 1-Year Supplemental Estimates
      description: Query ACS 1-Year Supplemental Estimates for geographies with 20,000+ population.
      operationId: getAcs1Supplemental
      tags:
      - ACS
      parameters:
      - $ref: '#/components/parameters/VintagePath'
      - $ref: '#/components/parameters/GetParam'
      - $ref: '#/components/parameters/ForParam'
      - $ref: '#/components/parameters/InParam'
      - $ref: '#/components/parameters/KeyParam'
      responses:
        '200':
          description: ACS Supplemental result set
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DataMatrix'
components:
  responses:
    BadRequest:
      description: Malformed query — for example a missing required parameter, unknown variable, or invalid geography clause.
      content:
        text/html:
          schema:
            type: string
    NotFound:
      description: Dataset, vintage, or variable not found.
      content:
        text/html:
          schema:
            type: string
  parameters:
    VintagePath:
      name: vintage
      in: path
      required: true
      description: Year (or year+month combination) identifying the dataset vintage. Example values include `2024`, `2023`, `2020`.
      schema:
        type: string
        pattern: ^[0-9]{4}([0-9]{2})?$
        examples:
        - '2024'
    UcgidParam:
      name: ucgid
      in: query
      required: false
      description: Universal Census Geographic Identifier — alternate single-parameter geography selector.
      schema:
        type: string
        examples:
        - 0400000US06
    GetParam:
      name: get
      in: query
      required: true
      description: Comma-separated list of variables to retrieve. Use the group prefix `group(B19013)` to fetch every variable in a table.
      schema:
        type: string
        examples:
        - NAME,B01001_001E
    InParam:
      name: in
      in: query
      required: false
      description: Hierarchical filter for nested geographies (for example `state:06`).
      schema:
        type: string
        examples:
        - state:06
    ForParam:
      name: for
      in: query
      required: false
      description: Geography clause indicating the geographic level being queried (for example `state:*` or `county:001`).
      schema:
        type: string
        examples:
        - state:*
    KeyParam:
      name: key
      in: query
      required: true
      description: Free API key obtained at https://api.census.gov/data/key_signup.html
      schema:
        type: string
  schemas:
    DataMatrix:
      type: array
      description: '2-D JSON array. The first inner array is the header row of variable

        names; each subsequent inner array is a record whose elements align

        positionally with the header.

        '
      items:
        type: array
        items:
          type: string
      example:
      - - NAME
        - B01001_001E
        - state
      - - California
        - '39538223'
        - '06'
      - - Texas
        - '29145505'
        - '48'
  securitySchemes:
    ApiKeyQuery:
      type: apiKey
      in: query
      name: key
      description: Free API key obtained at https://api.census.gov/data/key_signup.html

US Census Bureau ACS API

Operations 5

Documentation

Specifications

Schemas & Data

Other Resources