Legal Land Descriptions and DMS
Property deeds in the US use metes-and-bounds descriptions or Public Land Survey System (PLSS) references. Boundary monuments and corners are defined with DMS coordinates: "a point located at 47°36'22\"N, 122°19'55\"W." These DMS values come from survey plats and must be converted to DD to locate the property on a map.
County Parcel GIS Data
Most US counties publish parcel GIS data downloadable as shapefiles or via ArcGIS Online. Parcel centroids are usually stored as WGS84 Decimal Degrees. If you receive a parcel file with UTM coordinates, you need to convert to DD to use it in Google Maps, Zillow's API, or any standard mapping tool.
MLS and Real Estate Listing Coordinates
The MLS (Multiple Listing Service) stores property coordinates in Decimal Degrees. Zillow, Redfin, and Realtor.com all use DD for display. When a listing address doesn't geocode correctly, agents manually enter DD coordinates — use a map to find the right coordinate and convert if needed.
Flood Zone and Elevation Certificates
FEMA flood zone determinations use coordinates to locate properties relative to Base Flood Elevations. Elevation certificates require the building's DD coordinate for the FEMA portal. Surveyor-provided coordinates in DMS or UTM need to be converted to DD for submission.
Coordinate Converter
—
—
—
—
—
—
—