HouseHunter
AlphaCompare U.S. residential hazards and county context with pinned public data and optional private home-cost imports.
Data Sources
HouseHunter pins source vintages for its local hazard map and county fit tools. Normal runs use verified caches and packaged ranking references; maintainer-only inputs are not live feeds. Home-market history is private, imported only by the user, and never published here.
This is a reviewed source inventory, not a live feed-health report. Availability depends on each app's configuration and the provider's current service.
Source Map Reviewed · Project Source Evidence (opens in a new tab)
Core hazard map
FEMA National Risk Index
Role: Separate tract and county building-loss inputs for 17 hazards; HouseHunter derives residential hazard percentiles at each grain.
Availability: Pinned v1.20 (December 2025) ArcGIS tract and county layers. Runtime downloads verify revisions and cache them locally.
Coverage: 85,154 tracts and 3,232 counties/county equivalents in the pinned source layers.
County Health Rankings & Roadmaps 2025
Role: Official county Community Conditions Health Group plus a separate NPPES-derived mental-health supplement used in County Fit.
Availability: Pinned 2025 ArcGIS county layer and 2025 supplemental file; the supplement is acquired by maintainers, not at app startup.
Official Source for County Health Rankings & Roadmaps 2025 (opens in a new tab)Community Conditions county layer (opens in a new tab)Mental-health supplement (opens in a new tab)2025 county conditions guide for County Health Rankings & Roadmaps 20252025 provider supplement guide for County Health Rankings & Roadmaps 2025
County fit and context
BEA Regional Price Parities
Role: 2024 MSA all-items RPP for the map and county fit; official state RPP supplements nonmetro ranking assignments.
Availability: Pinned MARPP and SARPP 2024 archives. BEA map context is optional and can be null when its verified download fails.
Private local input
Realtor.com Research Data
Role: County home-cost month and trailing-12-month history for Home Costs, Affordability, and Custom Fit.
Availability: Private, explicit local import of a checksum-approved file for acknowledged personal use. No rows are packaged, fetched automatically, or exposed by this site.
Reuse is restricted and the data is available only through the user's private local import.
Pinned county ranking
Census Population Estimates Program
Role: 2025 county population for ranking eligibility and context, including the fixed 25,000-person floor.
Availability: Pinned 2025 county totals, acquired by maintainers and packaged only as derived county reference values.
FBI Crime Data Explorer
Role: 2023–2025 attributed agency crime and reporting-population coverage for Safety Factors.
Availability: Pinned agency response manifest and manually staged reference archives; suppression and less than 90% coverage remain null.
EPA Safe Drinking Water Information System
Role: Public-water-system inventory and violation records contributing to Safety Factors.
Availability: Pinned 2026Q2 bulk submission staged by maintainers; excludes private wells and is not real-time water-quality measurement.
EPA Community Water System Service Areas
Role: Modeled and supplied public-water boundaries allocated to 2020 Census block population for county coverage context.
Availability: Pinned version 2.1 GeoPackage and block table, acquired by maintainers; insufficient allocatable coverage remains null.
HRSA Area Health Resources Files
Role: 2024–2025 county primary-care and dental provider supply for Health utility.
Availability: Pinned AHRF archive acquired by maintainers; provider counts are availability proxies.
Census ACS 2024 Five-Year Estimates
Role: Housing age/value and property tax, commute context, and county-to-CBSA geography used by the ranking and housing-stock references.
Availability: Pinned table-based summary files B25034, B25035, B25103, B25077, and B08303; maintainer-generated housing-stock assets are bundled, not fetched at runtime.
Coverage: Tract and county housing stock across the 50 states, DC, and Puerto Rico; separate county ranking inputs.
BLS Quarterly Census of Employment and Wages
Role: County employment and wage context for Opportunity utility.
Availability: Pinned final 2024 and 2025 county high-level archives acquired by maintainers.
FCC Broadband Data Collection
Role: December 2025 terrestrial fixed 100/20 served share of broadband-serviceable locations for Opportunity utility.
Availability: Pinned county summary archive staged by maintainers; Location Fabric is denied and this is not population coverage.
NOAA U.S. Climate Normals
Role: 1991–2020 annual and monthly in-county station climate values for optional filters.
Availability: Pinned v1.0.1 station archives acquired by maintainers; climate is null without a fully qualifying station.
Appalachian Regional Commission county list
Role: Appalachia region membership for County Fit filters.
Availability: Reviewed 2026 county list packaged as a fixed FIPS reference.
State homeschool law references
Role: Official state statute references inform HouseHunter's approximate, project-authored Homeschool Policy Fit rubric.
Availability: Pinned state-level rubric reviewed 2026-09-16; it is a preference proxy, not legal advice or current compliance guidance.
Coverage: 50 states and DC; the pinned rubric contains each jurisdiction's official statute URL.
Official Source for State homeschool law references (opens in a new tab)51 Pinned Official Statute Citations (opens in a new tab)A project-authored preference rubric is outside the external dataset catalog.
Geography and mountain inputs
Census TIGER/Line
Role: 2025 county boundaries for ranking and 2020 census blocks with population/internal points for Mountain Magnitude.
Availability: Pinned 2025 national county ZIP plus 51 state/DC 2020 block extracts; Mountain build is maintainer-only.
Coverage: 50 states and DC; 2020 block and 2025 county vintages are kept distinct.
USGS 3D Elevation Program
Role: Elevation rasters for Mountain Magnitude terrain relief, slope, and ruggedness.
Availability: Pinned 1,645 reviewed 1-arc-second tiles; maintainer-only acquisition and no normal startup fetch.
USGS Protected Areas Database
Role: PAD-US 4.1 public-access polygons for Mountain Magnitude open-land context.
Availability: Pinned anonymous MapServer object inventory; maintainer-only capture.
USGS National Transportation Database trails
Role: Mapped hiking trail segments for Mountain Magnitude access distance and density.
Availability: Pinned 51 state/DC GPKG extracts dated 2026-02-12; maintainer-only build input.
On-demand address lookup
Census Geocoder
Role: Matches a user-entered address or fallback coordinates to its 2020 Census tract.
Availability: Called only on explicit lookup; a provider outage is not treated as an empty match.
OpenStreetMap Nominatim
Role: Fallback street search only when Census returns a valid empty address-match list; Census still supplies the tract ID.
Availability: Optional HTTPS endpoint, disableable by operator; approximate road matches require user confirmation.