Data Sources & Methodology
We combine official government data with statistical modeling to provide comprehensive ZIP code insights. Below is a detailed breakdown of our data sources and methodology.
Data Transparency Notice
Official Data Sources: Demographics, housing, weather, and crime data come directly from official U.S. government APIs (Census Bureau for demographics/housing, NOAA for weather/climate, FBI for crime statistics).
Modeled Estimates: Schools and some economic indicators are currently modeled estimates based on national averages and regional patterns. School data integration with IPEDS is in progress.
U.S. Census Bureau ✅ ACTIVE
We actively query the Census Bureau API to retrieve real-time demographic and housing statistics from the American Community Survey (ACS) 5-Year Estimates. This is OFFICIAL GOVERNMENT DATA.
Data Points Included:
- ✅ Population totals and trends
- ✅ Age distribution and median age
- ✅ Race and ethnicity breakdown
- ✅ Educational attainment levels
- ✅ Household income and per capita income
- ✅ Home values and rent prices
- ✅ Housing types and occupancy rates
- ✅ Household size and composition
NOAA Weather Data ✅ ACTIVE
We actively query the National Oceanic and Atmospheric Administration (NOAA) API to retrieve official climate normals, temperature data, and precipitation statistics. This data comes from the nearest weather station to each ZIP code and represents 30-year climate averages (1991-2020).
Data Points Included:
- ✅ Average monthly temperatures (NOAA official)
- ✅ Annual precipitation totals (NOAA official)
- ✅ Climate normals from nearest weather station
- ✅ Real-time API integration
- ✅ 30-year historical averages
- ✅ Temperature and precipitation data
FBI Crime Data ✅ ACTIVE
We actively query the FBI Crime Data Explorer API to retrieve official state-level crime statistics. Data includes violent crime, property crime, and detailed offense breakdowns. We use state-level rates to estimate ZIP code-level crime based on population. This is OFFICIAL FBI DATA.
Data Points Included:
- ✅ Violent crime rates (FBI official)
- ✅ Property crime statistics (FBI official)
- ✅ Murder, rape, robbery, assault rates
- ✅ Burglary, larceny, motor vehicle theft
- ✅ State-level official data
- ✅ Real-time API integration
School Data ⚙️ MODELED
School data is currently modeled with representative school names, enrollments, and performance metrics. For accurate school information, please verify with GreatSchools.org or your local school district.
Data Points Included:
- ⚙️ Modeled school listings
- ⚙️ Estimated enrollment numbers
- ⚙️ Modeled student-teacher ratios
- ⚙️ Estimated performance metrics
- ⚙️ Representative school types
- ⚙️ Working on NCES data integration
Economic Data ⚙️ MODELED
Income data comes from Census Bureau (official), while employment rates and industry breakdowns are currently modeled. We are working to integrate Bureau of Labor Statistics API for official employment data.
Data Points Included:
- ✅ Median income (Census - official)
- ⚙️ Unemployment rates (modeled)
- ⚙️ Employment by industry (modeled)
- ⚙️ Estimated wage data
- ⚙️ Modeled labor force statistics
- ⚙️ Working on BLS API integration
About Data Accuracy & Methodology
Official Government Data: Demographics, housing, and weather statistics are retrieved in real-time from official U.S. government APIs: Census Bureau (American Community Survey 5-Year Estimates) for demographics/housing, and NOAA (National Oceanic and Atmospheric Administration) for weather/climate data. This data is official, unmodified, and comes directly from government sources.
Modeled Estimates: Schools, crime, and some economic metrics are currently generated using statistical models based on national averages, regional patterns, and population density. These are directionally accurate estimates but should not be used for critical decisions without verification.
ZIP Code vs. ZCTA: The Census Bureau uses ZIP Code Tabulation Areas (ZCTAs), which are statistical representations of ZIP codes. Our data uses ZCTAs for Census statistics.
Data Lag: Census data typically has a 1-2 year lag between collection and publication. We query the most recent available ACS 5-Year Estimates.
For Critical Decisions: While demographics, housing, and weather data come from official government sources, always verify school data with GreatSchools.org or your local school district, and crime data with local law enforcement before making major decisions like relocation or real estate investments.
Citing Our Data
If you use data from ZipCode-Data.com in your research or publications, please cite both our website and the original data source. For example: "Data sourced from ZipCode-Data.com, compiled from U.S. Census Bureau American Community Survey 5-Year Estimates (2018-2022)."