geoprimsField-grade geospatial math

State plane coordinates

State plane coordinates (SPCS83).

These tools convert between NAD 83 latitude and longitude and State Plane Coordinate System of 1983 eastings and northings, and find which zone covers a place. US surveyors, engineers, and county GIS staff use them for deeds, plats, and project control. Start with the zone lookup, then convert. The costly pitfall is the foot: US survey feet and international feet differ by 2 parts per million, which is feet on a state plane coordinate.

I want to find the state plane zone for a place

I want to convert between latitude and longitude and state plane

Working in state plane

  1. Find the zone for the job from the state and county, or from a point. State plane zone lookup
  2. Convert latitude and longitude to northing and easting in that zone, in its legal unit. Latitude and longitude to state plane (SPCS83)
  3. Grid distances are not ground distances: the combined factor scales between them. Combined scale factor (grid and ground)

Guides that use these tools