Public land and infrastructure data
for any US location, in one call.

Send a coordinate or an address. Get back 351 facts drawn from 95 public sources (flood zones, terrain, soils, grid and pipelines, hazards, broadband, demographics and more), each with its source, license and attribution.

Read the quickstart Browse 351 fields

curl https://api.isopleth.dev/v1/fetch \
  -H "Authorization: Bearer $ISOPLETH_KEY" \
  -H "Content-Type: application/json" \
  -d '{"lat": 30.2672, "lng": -97.7431,
       "fields": ["elevation", "slope_degrees", "nearest_substation_distance_m"]}'

{
  "lat": 30.2672, "lng": -97.7431, "fetched_at": "2026-10-28T17:02:11Z",
  "resolved_location": {"lat": 30.2672, "lng": -97.7431, "source": "coordinate"},
  "fields": {
    "elevation": {"value": 151.2, "unit": "meters", "status": "ok", "confidence": "high",
                  "source": "USGS_3DEP", "dataset_vintage": "3DEP 1/3 arc-second",
                  "license": "US federal public domain", "attribution": "U.S. Geological Survey",
                  "fetched_at": "2026-10-28T17:02:11Z", "ttl_seconds": 31536000, "notes": null},
    "slope_degrees": {"value": 2.4, "unit": "degrees", "status": "ok", "...": "..."},
    "nearest_substation_distance_m": {"value": 1840.0, "unit": "meters", "status": "ok", "...": "..."}
  },
  "partial_failures": [],
  "attributions": [
    {"source": "EIA_POWER", "license": "US federal public domain",
     "attribution": "U.S. Energy Information Administration", "fields": ["nearest_substation_distance_m"]},
    {"source": "USGS_3DEP", "license": "US federal public domain",
     "attribution": "U.S. Geological Survey", "fields": ["elevation", "slope_degrees"]}
  ]
}

One schema

Every field returns a value, unit, status, source, license and attribution, so you can cite it and you know when something is missing.

Presets for common jobs

Pick a bundle such as boundaries or flood_risk instead of listing fields one by one.

Batch and geocode

Up to 100 locations per batch request, plus a US address geocoder. Pay only for lookups that return data.

Pricing

Free

$0 / month

1,000 lookups per month

10 requests / minute
Batches up to 10 locations
Up to 1 API key
No card needed

Starter

$19 / month

20,000 lookups per month

60 requests / minute
Batches up to 100 locations
Up to 5 API keys
For a product or internal tool

Pro

$79 / month

120,000 lookups per month

300 requests / minute
Batches up to 100 locations
Up to 20 API keys
For production workloads

Top-up

$10 one-time

5,000 extra lookups

Works on any plan
Valid 365 days
Used after your monthly allowance

A lookup is one location with up to 50 fields; larger requests count one lookup per started block of 50 fields. Requests that return no data are not charged. Prices exclude any applicable sales tax, which is shown at checkout. Monthly plans renew until you cancel in the billing portal. How lookups and billing work.

Built on public data

Isopleth reads from U.S. federal and state agencies (USGS, FEMA, EPA, EIA, NOAA, USDA, Census, FCC, FAA and others) and open-data projects such as OpenStreetMap and Overture Maps. Every response names its sources and licenses. See sources and licenses.

Isopleth is a screening tool. Public data can be incomplete or out of date, and results are not a survey, title search, appraisal, engineering study or legal advice.

Public land and infrastructure datafor any US location, in one call.