{"sources":[{"id":"census_zcta","name":"US Census Bureau TIGER/Line ZIP Code Tabulation Areas (2020 delineation)","vintage":"tiger_2025 / gazetteer_2024","licence":"public domain (17 U.S.C. 105)","attribution":"Boundaries and internal points: U.S. Census Bureau, TIGER/Line and Gazetteer files. Wi-Fi access points: Road-Warrior observation database.","url":"https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.html","covers":["AS","GU","MP","PR","US","VI"]},{"id":"roadwarrior_wifi_ap","name":"Road-Warrior Wi-Fi access-point observations","vintage":"continuous","licence":"proprietary","attribution":"Road-Warrior Geo API","covers":["AS","GU","MP","PR","US","VI"]}],"sampling":"uniform over observed Wi-Fi APs inside the area (density-proportional), displaced uniformly within a disc","postal_data_version":"tiger_2025/gazetteer_2024","reproducibility_scope":"api_key+postal_area+pool_version","location_methods":[{"location_method":"wifi_observation_sample","ap_backed":true,"description":"a Wi-Fi AP observed inside the area, displaced within a disc"},{"location_method":"census_internal_point","ap_backed":false,"description":"the Census internal point for the area, displaced within a disc"},{"location_method":"postal_centroid","ap_backed":false,"description":"the Census internal point itself, undisplaced"}],"processing_modes":[{"processing_mode":"precomputed_pool","description":"density-proportional draw from the precomputed AP pool"},{"processing_mode":"live_probe","description":"nearest AP to a probe inside the area, used when no pool exists"},{"processing_mode":"none","description":"no AP was involved; the coordinate came from Census geometry"}],"warning_codes":[{"code":"no_precomputed_pool","description":"This postal area has no precomputed AP pool; a fallback source was used."},{"code":"pool_rebuilt_mid_request","description":"The AP pool was rebuilt between reading its version and drawing from it."},{"code":"fallback_source_used","description":"A fallback rung supplied the coordinate instead of the precomputed pool."},{"code":"no_ap_backed_coordinate","description":"No usable Wi-Fi AP inside the area; the coordinate is not AP-backed."},{"code":"undisplaced_postal_centroid","description":"The Census internal point itself was returned, undisplaced."},{"code":"coordinate_outside_postal_area","description":"A returned coordinate falls outside the postal polygon after rounding."},{"code":"no_delivery_geometry","description":"The USPS ZIP exists but has no delivery area (PO Box, unique or military), so the Census never drew a polygon for it."},{"code":"point_count_reduced","description":"Fewer distinct coordinates were available than the caller asked for."},{"code":"large_postal_area","description":"The postal area is unusually large, so an area-level coordinate is a weak locator."}],"methods":[{"method":"ap_pool","ap_backed":true,"location_method":"wifi_observation_sample","processing_mode":"precomputed_pool","description":"precomputed density-proportional draw over APs inside the area"},{"method":"ap_live","ap_backed":true,"location_method":"wifi_observation_sample","processing_mode":"live_probe","description":"nearest AP to a probe inside the area, used when no pool exists"},{"method":"census_internal_point","ap_backed":false,"location_method":"census_internal_point","processing_mode":"none","description":"Census internal point, displaced within a disc"},{"method":"centroid","ap_backed":false,"location_method":"postal_centroid","processing_mode":"none","description":"Census internal point itself, undisplaced"}],"notes":["United States only. Every other country returns 404 unsupported_country.","Coordinates are area-level, never address-level, and are not evidence that any person or device was at or near the returned point."],"meta":{"request_id":"rq_bfc13116da7192a1","api_version":"v2"}}