API for NGS’s Coordinate Conversion and Transformation Tool (NCAT)

NGS Coordinate Conversion and Transformation Tool (NCAT) allows users to easily convert between different coordinate systems and/or transform between different reference frames and/or datums, in a single step. For coordinate conversion, NCAT allows conversion between lat/long/height, SPC, UTM, XYZ, and USNG systems. NCAT currently uses NADCON 5.0 to perform three-dimensional (latitude, longitude, ellipsoid height) coordinate transformations and VERTCON 3.0 to perform orthometric height transformations. Transformations are provided for a wide range of frames/datums and regions in the National Spatial Reference System. NADCON and VERTCON provide local error estimates for each transformation, and do not support transformations which are outside the boundaries of the supported areas (generally, CONUS, Alaska, Hawaii, Puerto Rico and the US Virgin Islands, American Samoa, and Guam and Northern Mariana Islands).

Please note that, although either orthometric or ellipsoidal heights can be used as inputs to NCAT, at this time NCAT does not convert between orthometric and ellipsoidal heights. Only orthometric-to-orthometric and ellipsoidal-to-ellipsoidal height transformations are currently possible in NCAT.

Metadata

The following URL provides metadata for various parameters used in the JSON response: https://geodesy.noaa.gov/api/ncat/meta

Reference Frames (historically called “horizontal datum”) Supported for Transformation

Region

Valid Reference Frames

StGeorge

SG1897, SG1952, NAD83(1986)

StPaul

SP1897, SP1952, NAD83(1986)

StLawrence

SL1952, NAD83(1986)

Alaska

NAD27, NAD83(1986), NAD83(1992), NAD83(NSRS2007), NAD83(2011)

Conus

USSD, NAD27, NAD83(1986), NAD83(HARN), NAD83(FBN), NAD83(NSRS2007), NAD83(2011)

Hawaii

OHD, NAD83(1986), NAD83(1993), NAD83(PA11)

PRVI

PR40, NAD83(1986), NAD83(1993), NAD83(1997), NAD83(2002), NAD83(NSRS2007), NAD83(2011)

AS

AS62, NAD83(1993), NAD83(2002), NAD83(PA11)

GuamCNMI

GU63, NAD83(1993), NAD83(2002), NAD83(MA11)


Geopotential Datums (historically called “vertical datum”) Supported for Transformation

Region

Valid Geopotential Datums

Conus

NGVD29, NAVD88

Alaska

NGVD29, NAVD88

Guam

GUVD63, GUVD04

CNMI

LT, NMVD03

VI

LT, VIVD09

PR

LT, PRVD02

AS

LT, ASVD02