# Land Survey Screening

Elevation, slope, flood zone and wetlands screening for any US coordinate, plus distance, area and sun-time helpers.

## 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://land-survey.x402tookit.com/openapi.json
- x402 manifest: https://land-survey.x402tookit.com/.well-known/x402
- Catalog (free): https://land-survey.x402tookit.com/catalog
- Health (free): https://land-survey.x402tookit.com/health
- Uptime (free): https://land-survey.x402tookit.com/uptime

## Endpoints (8)

### GET /distance-bearing — $0.02
Great-circle distance (miles, km, feet, nautical miles) and initial compass bearing between two latitude/longitude points.
Params: lat1: number, lon1: number, lat2: number, lon2: number
Example: https://land-survey.x402tookit.com/distance-bearing?lat1=40.6413&lon1=-73.7781&lat2=33.9416&lon2=-118.4085

### GET /elevation-profile — $0.03
Elevation profile along a line between two US points: relief, ascent, descent, steepest grade and a flat/steep verdict.
Params: lat1: number, lon1: number, lat2: number, lon2: number, points?: integer
Example: https://land-survey.x402tookit.com/elevation-profile?lat1=39.7392&lon1=-104.9903&lat2=39.7392&lon2=-105.2&points=6

### GET /elevation — $0.02
Ground elevation in feet and meters at a US latitude and longitude from USGS 3DEP, with data-coverage check.
Params: lat: number, lon: number
Example: https://land-survey.x402tookit.com/elevation?lat=39.7392&lon=-104.9903

### GET /flood-zone — $0.02
FEMA flood hazard zone at a US latitude and longitude: high-risk (A/AE/V), moderate or minimal, with base flood elevation.
Params: lat: number, lon: number
Example: https://land-survey.x402tookit.com/flood-zone?lat=25.7617&lon=-80.1918

### GET /polygon-area — $0.02
Area in acres, hectares and square meters and perimeter of a polygon from lat,lon vertices, e.g. a parcel or flight area.
Params: points: string
Example: https://land-survey.x402tookit.com/polygon-area?points=39.7400%2C-104.9900%3B39.7400%2C-104.9850%3B39.7360%2C-104.9850%3B39.7360%2C-104.9900

### GET /site-screen — $0.05
First-look site screen for a US coordinate: elevation, FEMA flood zone and mapped wetlands combined, with flags.
Params: lat: number, lon: number
Example: https://land-survey.x402tookit.com/site-screen?lat=25.7617&lon=-80.1918

### GET /sun-times — $0.02
Sunrise, sunset, civil twilight and day length for a latitude/longitude and date, in UTC and a chosen UTC offset.
Params: lat: number, lon: number, date?: string, utc_offset_hours?: number
Example: https://land-survey.x402tookit.com/sun-times?lat=39.7392&lon=-104.9903&date=2026-06-21&utc_offset_hours=-6

### GET /wetlands-check — $0.02
Is a US point inside a mapped wetland? National Wetlands Inventory type and size, as a permitting heads-up.
Params: lat: number, lon: number
Example: https://land-survey.x402tookit.com/wetlands-check?lat=25.7&lon=-80.9

## Terms

Screening results computed from USGS 3DEP elevation, FEMA National Flood Hazard Layer and US Fish and Wildlife National Wetlands Inventory public data, provided as is. Maps can be outdated or imprecise. This is NOT a land survey, flood zone determination, wetland delineation, permit or legal opinion; do not rely on it for construction, insurance, lending or regulatory decisions. Not affiliated with or endorsed by USGS, FEMA or USFWS. Each answer gives its source endpoint (sourceUrl) and access time (asOf).