How to hit the Data USA API

Data USA at https://api.datausa.io/tesseract serves US Census and other public data as cubes you query by measure and drilldown.

Authentication

None — no key, no signup. Every example runs as-is.

Full reference: https://datausa.io/about/api/

Population by state

curl "https://api.datausa.io/tesseract/data.jsonrecords?cube=acs_yg_total_population_5&drilldowns=State,Year&measures=Population&limit=2"
Run in PostTaco
Example response (trimmed) 
{
  "annotations": {
    "subtopic": "Demographics",
    "table_id": "B01003",
    "dataset_name": "ACS 5-year Estimate",
    "topic": "Diversity",
    "source_description": "The American Community Survey (ACS) is conducted by the US Census and sent to a portion of the population every year.",
    "dataset_link": "http://www.census.gov/programs-surveys/acs/",
    "source_name": "Census Bureau"
  },
  "page": {
    "limit": 2,
    "offset": 0,
    "total": 624
  },
  "columns": [
    "State ID",
    "State"
  ],
  "data": [
    {
      "State ID": "04000US01",
      "State": "Alabama",
      "Year": 2013,
      "Population": 4799277
    },
    {
      "State ID": "04000US01",
      "State": "Alabama",
      "Year": 2014,
      "Population": 4817678
    }
  ]
}