# US Geography

Geocode US addresses, reverse geocode, districts, metro areas, ZIP lookup, state FIPS and GEOID parsing.

## How to pay

Machine-payable over x402. USDC on: Base (eip155:8453), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp), Polygon (eip155:137), Arbitrum One (eip155:42161).
No accounts. No API keys. No signup. The paying wallet is the account.

## Machine-readable

- OpenAPI: https://geo-us.x402tookit.com/openapi.json
- x402 manifest: https://geo-us.x402tookit.com/.well-known/x402
- Catalog (free): https://geo-us.x402tookit.com/catalog
- Health (free): https://geo-us.x402tookit.com/health
- Uptime (free): https://geo-us.x402tookit.com/uptime

## Endpoints (8)

### GET /coord-distance — $0.02
Great-circle (haversine) distance between two coordinates in km, miles and nautical miles, with bearing and midpoint.
Params: lat1: number, lon1: number, lat2: number, lon2: number
Example: https://geo-us.x402tookit.com/coord-distance?lat1=40.7128&lon1=-74.006&lat2=34.0522&lon2=-118.2437

### GET /geocode-address — $0.02
Geocode a US street address: normalized address, latitude and longitude, state, county and tract codes, with match quality.
Params: address: string
Example: https://geo-us.x402tookit.com/geocode-address?address=1600+Pennsylvania+Ave+NW%2C+Washington%2C+DC+20500

### GET /geoid-parse — $0.02
Parse a Census GEOID into state, county, tract, block group and block codes and name its geographic level.
Params: geoid: string
Example: https://geo-us.x402tookit.com/geoid-parse?geoid=110019800001034

### GET /metro-area — $0.02
Metro area context for a US address or lat/lon: metro or micropolitan area, urban area, county and urban or rural setting.
Params: address?: string, lat?: number, lon?: number
Example: https://geo-us.x402tookit.com/metro-area?address=1600+Pennsylvania+Ave+NW%2C+Washington%2C+DC+20500

### GET /political-districts — $0.05
Congressional and state legislative (upper and lower) districts covering a US address, with district codes and the state.
Params: address: string
Example: https://geo-us.x402tookit.com/political-districts?address=1600+Pennsylvania+Ave+NW%2C+Washington%2C+DC+20500

### GET /reverse-geocode — $0.02
Census geography at a US coordinate: state, county, tract, block, city or place, with GEOIDs for joining Census data.
Params: lat: number, lon: number
Example: https://geo-us.x402tookit.com/reverse-geocode?lat=38.8977&lon=-77.0365

### GET /us-state-info — $0.02
Look up a US state or territory by name, postal abbreviation or FIPS code: all three, region, division and capital.
Params: state: string
Example: https://geo-us.x402tookit.com/us-state-info?state=OH

### GET /zip-lookup — $0.02
US ZIP code to place name, state and centroid; optionally verify it belongs to a state you expect.
Params: zip: string, state?: string
Example: https://geo-us.x402tookit.com/zip-lookup?zip=90210&state=CA

## Terms

Geographic facts come from the US Census Bureau geocoder and Zippopotam.us and local computation, provided as is. Address matches are approximate and based on Census address ranges, not parcel data, and boundaries change with each vintage. Addresses sent in a query are personal data you choose to disclose; do not send other people's home addresses without a reason. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.