US Census

The US Census Bureau Data API provides programmatic access to a wide range of public datasets, including the American Community Survey (ACS), the Decennial Census, Population Estimates, County Business Patterns, and small-area income, poverty, and health insurance estimates. This connector lets you ingest US Census data into Nexla as a source using pre-built endpoint templates. Requests are authenticated with an API key issued by the Census Bureau developer portal.

Power end-to-end data operations for your US Census API with Nexla. Our bi-directional US Census connector is purpose-built for US Census, making it simple to ingest data, sync it across systems, and deliver it anywhere — all with no coding required. Nexla turns API-sourced data into ready-to-use, reusable data products and makes it easy to send data to US Census or any other destination. With comprehensive monitoring, lineage tracking, and access controls, Nexla keeps your US Census workflows fast, secure, and fully governed.

Features

Type: API

SourceDestination

• Seamless API Integration: Connect to any endpoint as source or destination without coding, with automatic data product creation
• Visual Composition & Chaining: Build complex integrations using visual templates, chain API calls, and compose workflows with data validation and filtering
• API Proxy: Expose curated slices of your data securely with a secure and customizable API proxy that validates and transforms data on the fly
• Request optimization with intelligent batching, retry, and caching to minimize API calls and costs

Prerequisites

Before creating a US Census credential, you need an API key issued by the US Census Bureau. The key is free and is passed as the key query parameter on every request to api.census.gov.

To obtain your API key, follow these steps:

1. Go to the Census Bureau API key signup page at https://api.census.gov/data/key_signup.html.

2. Provide the requested details, which include your organization name and email address, and agree to the terms of service.

3. Submit the form. The Census Bureau will email you an activation link.

4. Open the activation email and follow the link to activate your key. Copy the key value and store it securely, as you will enter it when creating your Nexla credential.

For more information about the available datasets and how requests are structured, see the US Census Data API documentation.

Authenticate

Credentials required

Field	Required	Secret	Description
API Key	Yes	Yes	API key issued by the US Census Bureau developer portal.

Create a credential in Nexla

1. After selecting the data source type, click the Add Credential tile to open the Add New Credential overlay.

2. Enter a name for the credential in the Credential Name field and a short, meaningful description in the Credential Description field.

3. Enter your API key in the API Key field. This is the key issued by the US Census Bureau developer portal, and it is sent as the key query parameter on every request to the Census Data API.

   Your API key authenticates all requests to the US Census Data API. Keep it confidential. If it is compromised, request a new key from the Census Bureau signup page.

4. Click the Save button at the bottom of the overlay. The newly added credential will now appear in a tile on the Authenticate screen during data source creation.

Use as a data source

To create a new data flow, navigate to the Integrate section, and click the New Data Flow button. Select the US Census connector tile, then select the credential that will be used to connect to the Census Data API, and click Next; or, create a new US Census credential for use in this flow.

Endpoint templates

Nexla provides pre-built templates that can be used to rapidly configure data sources to ingest data from common US Census endpoints. Select the endpoint from which this source will fetch data from the Endpoint pulldown menu. Most templates take a Year parameter, which is the vintage year of the dataset (for example, 2021). Available endpoint templates are listed in the expandable boxes below.

[Rest API] List ACS 5-Year Detailed Tables

Retrieve American Community Survey 5-Year detailed table estimates.

• Provide the vintage Year for the dataset (for example, 2021). Detailed tables provide the most granular ACS estimates across a broad range of population and housing topics.

[Rest API] List ACS 5-Year Subject Tables

Retrieve American Community Survey 5-Year subject table estimates.

• Provide the vintage Year for the dataset (for example, 2021). Subject tables present ACS data as pre-computed estimates and percentages organized by topic.

[Rest API] List ACS 5-Year Data Profiles

Retrieve American Community Survey 5-Year data profile estimates.

• Provide the vintage Year for the dataset (for example, 2021). Data profiles summarize social, economic, housing, and demographic characteristics for a geography in a single view.

[Rest API] List ACS 1-Year Detailed Tables

Retrieve American Community Survey 1-Year detailed table estimates.

• Provide the vintage Year for the dataset (for example, 2021). The 1-Year estimates cover areas with populations of 65,000 or more and reflect the most current single-year data.

[Rest API] List ACS Migration Flows

Retrieve American Community Survey migration flows data by county.

• Provide the vintage Year for the dataset (for example, 2021). Migration flows describe county-to-county movement of residents over the survey period.

[Rest API] List ACS 5-Year Variables

List the variables available for the ACS 5-Year dataset.

• Provide the vintage Year for the dataset (for example, 2021). Use this template to discover the variable codes and labels you can request from the ACS 5-Year detailed tables.

[Rest API] List ACS 5-Year Geography Levels

List the supported geography levels for the ACS 5-Year dataset.

• Provide the vintage Year for the dataset (for example, 2021). Use this template to discover the geography levels (nation, state, county, and below) that the ACS 5-Year dataset supports.

[Rest API] List Decennial DHC Data

Retrieve 2020 Decennial Demographic and Housing Characteristics data.

• Provide the vintage Year for the dataset (for example, 2020). The DHC file provides detailed population and housing counts from the 2020 Decennial Census.

[Rest API] List Decennial Redistricting Data

Retrieve 2020 Decennial Redistricting Data (PL 94-171).

• Provide the vintage Year for the dataset (for example, 2020). The PL 94-171 file provides the population counts used for legislative redistricting.

[Rest API] List Population Estimates

Retrieve Population Estimates Program (PEP) data.

• Provide the vintage Year for the dataset (for example, 2021). PEP provides annual population totals for the nation, states, counties, and other geographies between censuses.

[Rest API] List Population Estimates Components

Retrieve Population Estimates Program components-of-change data.

• Provide the vintage Year for the dataset (for example, 2021). Components-of-change data break population change into births, deaths, and net migration.

[Rest API] List County Business Patterns

Retrieve County Business Patterns (CBP) data.

• Provide the vintage Year for the dataset (for example, 2021). CBP reports establishment counts, employment, and payroll by industry and geography.

[Rest API] List Annual Business Survey

Retrieve Annual Business Survey (ABS) company summary data.

• Provide the vintage Year for the dataset (for example, 2021). ABS reports statistics on employer businesses, including characteristics of owners.

[Rest API] List ACS 5-Year Microdata (PUMS)

Retrieve American Community Survey 5-Year Public Use Microdata Sample (PUMS).

• Provide the vintage Year for the dataset (for example, 2021). PUMS provides individual, anonymized records for custom tabulation at the state level.

[Rest API] List Nonemployer Statistics

Retrieve Nonemployer Statistics data.

• Provide the vintage Year for the dataset (for example, 2021). Nonemployer Statistics cover businesses with no paid employees, such as sole proprietorships.

[Rest API] List Poverty (SAIPE) Estimates

Retrieve Small Area Income and Poverty Estimates (SAIPE) time series data.

• SAIPE provides annual income and poverty estimates for states, counties, and school districts. This template queries the SAIPE time series dataset.

[Rest API] List Health Insurance (SAHIE) Estimates

Retrieve Small Area Health Insurance Estimates (SAHIE) time series data.

• SAHIE provides model-based health insurance coverage estimates for states and counties. This template queries the SAHIE time series dataset.

Once the selected endpoint template has been configured, click the Test button to the right of the endpoint selection menu to retrieve a sample of the data that will be fetched. Sample data will be displayed in the Endpoint Test Result panel on the right, allowing you to verify that the source is configured correctly before saving.

Manual configuration

US Census data sources can also be manually configured to ingest data from any valid Census Data API endpoint, including datasets, variables, or geographies not covered by the pre-built templates, chained API calls, or custom request parameters. Select the Advanced tab at the top of the configuration screen, and follow the instructions in Connect to Any API to configure the API method, endpoint URL, date/time and lookup macros, path to data, metadata, and request headers.

Once all of the relevant settings have been configured, click the Create button in the upper right corner of the screen to save and create the new US Census data source. Nexla will now begin ingesting data from the configured endpoint and will organize any data that it finds into one or more Nexsets.