US data APIs
for your product
8 endpoints covering ZIP codes, SEC/EDGAR company data, ABA routing validation, EIN checks, US states, and federal holidays — everything US SaaS and fintech products need, in one API key.
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All 8 USA endpoints
All GET requests. Pass your API key in the X-API-Key header.
GETZIP code lookup/api/v1/usa/zipReturns city, state, state abbreviation, latitude, longitude, and country for any US ZIP code via Zippopotam.us
GETUS state information/api/v1/usa/state-infoReturns state name, capital, largest city, region, timezone, population, area, and statehood year for any of the 50 states + DC
GETUS federal holidays/api/v1/usa/federal-holidaysReturns all US federal holidays for a given year via Nager.Date
GETSEC EDGAR company lookup/api/v1/usa/sec-companyReturns company CIK, SIC code, industry, state of incorporation, fiscal year, and exchange listings from SEC EDGAR
GETUS area code lookup/api/v1/usa/area-codeReturns state, region, timezone, and type (geographic/toll-free) for a US telephone area code
GETEIN format validation/api/v1/usa/irs-ein-validateValidates US Employer Identification Number format (XX-XXXXXXX), checks IRS prefix ranges, returns formatted EIN
GETABA routing number validation/api/v1/usa/aba-routingValidates 9-digit ABA routing number checksum, identifies the bank, and returns the Federal Reserve district
GETUS population by state/api/v1/usa/census-populationReturns population, rank, approximate density, and year-over-year change for a US state or the national total
Starter code
Copy and paste. Works anywhere fetch runs.
Start building with the USA namespace
Free tier: 250 calls/month. No credit card. One API key for all 21 namespaces.