Frederick County, MD parcel and infrastructure data API

Parcel coverage in Frederick County

About 120,000 parcel records with boundaries, situs addresses and parcel numbers, with the latest source update from November 2026. Each record has a stable korzy_id you can store and look up again with /api/parcel-record. Share of records with each field:

Frederick County records do not include owner names. See pricing for credit costs.

Infrastructure in and around Frederick County

Example requests for Frederick County

Real responses from the production API, trimmed to the main fields. Every request needs an API key with api:read; see authentication and credits and limits.

1. Find a parcel by address

/api/search matches 437 N MARKET ST, FREDERICK, MD and returns the parcel's korzy_id, coordinates and record. 1 credit.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'q=437 N MARKET ST, FREDERICK, MD' \
  https://api.korzy.co/api/search

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/search",
    params={"q": "437 N MARKET ST, FREDERICK, MD"},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=30,
)
response.raise_for_status()
parcel = response.json()["results"][0]
print(parcel["korzy_id"], parcel["longitude"], parcel["latitude"])

{
  "results": [
    {
      "korzy_id": "24021-36637a7fe269f43a8b09",
      "address": "437 N MARKET ST",
      "city": "FREDERICK",
      "postcode": "21701",
      "county": "Frederick",
      "statefp": "24",
      "longitude": -77.41060606060569,
      "latitude": 39.4202246,
      "match_type": "exact",
      "parcelid": "0048 0112 0000 3",
      "parceladdr": "437 N MARKET ST",
      "parcelcity": "FREDERICK",
      "situs_zip": "21701",
      "usedesc": "Commercial",
      "land_use_code": "C",
      "zoning_code": "DB",
      "yearbuilt": 1900,
      "bldgsqft": 16119,
      "taxacres": 0.192,
      "land_value_usd": 235300,
      "improvement_value_usd": 1184400,
      "market_value_usd": 1419700,
      "saledate": "2022-07-13",
      "saleamt": 850000,
      "updated": "2026-11-03",
      "geoid": "24021"
    }
  ],
  "truncated": false
}

2. Look up the parcel at a point

/api/query/point returns every parcel whose boundary covers the coordinates; here it returns the same record, 24021-36637a7fe269f43a8b09, in records. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-77.410606' \
  --data-urlencode 'latitude=39.420225' \
  --data-urlencode 'limit=5' \
  https://api.korzy.co/api/query/point

const params = new URLSearchParams({"longitude": "-77.410606", "latitude": "39.420225", "limit": "5"});
const response = await fetch(`https://api.korzy.co/api/query/point?${params}`, {
  headers: { Authorization: `Bearer ${process.env.KORZY_API_KEY}` },
});
if (!response.ok) throw new Error(`Korzy API ${response.status}`);
const { records } = await response.json();
console.log(records.map((record) => record.korzy_id));

3. Check nearby data-center projects

/api/datacenters/context lists data-center projects within 10 km of the point, nearest first. 1 credit per 10 records requested.

curl --fail-with-body -sS --get \
  -H "Authorization: Bearer $KORZY_API_KEY" \
  --data-urlencode 'longitude=-77.410606' \
  --data-urlencode 'latitude=39.420225' \
  --data-urlencode 'radius_km=10' \
  --data-urlencode 'limit=3' \
  https://api.korzy.co/api/datacenters/context

import os
import requests

response = requests.get(
    "https://api.korzy.co/api/datacenters/context",
    params={"longitude": "-77.410606", "latitude": "39.420225", "radius_km": "10", "limit": "3"},
    headers={"Authorization": f"Bearer {os.environ['KORZY_API_KEY']}"},
    timeout=30,
)
response.raise_for_status()
for project in response.json()["projects"]:
    print(project["name"], project["status"], project["distance_km"])

{
  "projects": [
    {
      "project_id": "dc_04ab34ecac03ab2d6f75",
      "name": "Unnamed data center",
      "status": "unknown",
      "state": "MD",
      "longitude": -77.41160078667836,
      "latitude": 39.377725299999994,
      "location_precision": "footprint",
      "distance_km": 4.726530528064903
    }
  ],
  "radius_km": 10,
  "limit": 3,
  "truncated": false
}

Frederick County data questions

How many parcels in Frederick County include year built?

About 90,000 of about 120,000 parcel records (75%) include year built.

Does the Korzy API return owner names for Frederick County parcels?

Frederick County parcel records do not include owner names. Values, land use and building facts are returned where the county publishes them.

How many data-center projects are in Frederick County?

Korzy tracks 7 data-center projects in Frederick County: 3 under construction, 2 permitted and 1 operating. /api/datacenters/context lists projects within 10 km of any point.

How much power generation is in Frederick County?

9 operable power plants in Frederick County total about 85 MW of nameplate capacity, mainly solar and battery and pumped storage.

Which water systems serve Frederick County?

Service areas of about 35 community water systems cover about 8% of Frederick County, and sewer service areas cover about 14%. /api/utilities/context returns the water and sewer matches at a point.

More featured counties

• Montgomery County, MDBorders Frederick County · about 290,000 parcels
• Baltimore city, MDabout 240,000 parcels
• Prince George's County, MDabout 350,000 parcels
• Baltimore County, MDabout 370,000 parcels

All featured Maryland counties