Local ENU, NED, or AER to point
Finds the latitude, longitude, height, and position of a point given in a local tangent plane at an origin: east-north-up, north-east-down, or azimuth-elevation-range.
The point is at latitude 40.5095052756°, longitude -79.8991260647°, ellipsoidal height 1,179.34 m.
- Longitude
- Ellipsoidal height
- ECEF X
- ECEF Y, like -4819000 m
- ECEF Z, like 3976000 m
Provenance
- Computed by
- geodesy.frame.from-local 1.0.0, core 0.1.0
- Model
- Local east-north-up frame, WGS 84
- Accuracy
- Round trips within 1e-8 m for points within 1,000 km of the origin
- Notes
- None
- Cites
- Karney, C. F. F., GeographicLib, GeographicLib Geocentric and LocalCartesian classes
Something look off?
How we got thisFormula, worked example, sources, and proof
Model: Local offset rotated from the origin's east-north-up frame to ECEF, then Vermeille's closed-form inverse
Accuracy: Round trips within 1e-8 m for points within 1,000 km of the origin
When to use this: Use this when a point is described relative to a known station: east, north and up from an origin, north, east and down in an aircraft or vehicle frame, or as an azimuth, elevation and range from a total station or a tracker. It returns the point's latitude, longitude, height, and ECEF position.
Limitations: The local frame is tangent at the origin you give, so the further out the point lies the more the Earth's curvature matters; round trips stay within a hundredth of a micrometer out to a thousand kilometers. Heights are ellipsoidal. An azimuth here is true and geometric: it carries no refraction, no magnetic variation, and no instrument correction.
Worked example: 10 km out at 045°, 5° up. Source: GeographicLib LocalCartesian reverse of the AER offset.
You enter
- Azimuth
- 45 deg
- Elevation
- 5 deg
- Frame
- aer
- Origin height
- 300 m
- Origin latitude
- 40.446111 deg
- Origin longitude
- -79.982222 deg
- Slant range
- 10000 m
You get
- Latitude
- 40.5095052756°
- Longitude
- -79.8991260647°
- Ellipsoidal height
- 1,179.34 m
- ECEF X
- 851,837.223 m
- ECEF Y, like -4819000 m
- -4,781,764.412 m
- ECEF Z, like 3976000 m
- 4,121,928.515 m
Review: Not yet independently reviewed by a geodesist.
Last verified: 2026-09-18, when a maintainer last confirmed this tool's sources at the issuer. See the sources ledger.
Status: version 1.0.0, core 0.1.0. See this tool in the verification report.
Changes
- 2026-09-19, changed: The four frame conversions are stable: geodetic to ECEF and back, and to and from a local east-north-up frame. They reproduce the IOGP Guidance Note 7-2 worked examples and agree with GeographicLib's CartConvert within 15 nm on 1,000 ECEF points (poles to beyond geostationary orbit) and 500 local targets. Results are unchanged. Changelog
Checked against: 23 golden test vectors (download the test vectors, each with its source and tolerance). See how results are checked and every source.
Sources
- GeographicLib Geocentric and LocalCartesian classes, Karney, C. F. F., GeographicLib, GeographicLib 2.x. Geocentric.cpp: Vermeille's closed-form inverse; LocalCartesian.cpp: ENU rotation. Read free.
Terms
- AER: azimuth, elevation, range
- Direction and distance from a point: azimuth from north, elevation above the horizontal, and straight-line range. Source: GeographicLib
- ECEF: Earth-centered, Earth-fixed
- Cartesian X, Y, Z coordinates in meters from Earth's center, turning with the Earth. X points to 0° longitude on the equator and Z to the North Pole. Source: Department of Defense World Geodetic System 1984
- ENU: east, north, up
- Local Cartesian coordinates centered on a chosen point, with axes toward east, north, and up. Source: GeographicLib
- NED: north, east, down
- Local Cartesian axes toward north, east, and down, as aircraft navigation uses them. Source: GeographicLib
ECEF — Earth-centered, Earth-fixed
Cartesian X, Y, Z coordinates in meters from Earth's center, turning with the Earth. X points to 0° longitude on the equator and Z to the North Pole.
Source: Department of Defense World Geodetic System 1984