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ENU (East/North/Up) to ECEF Converter

Converts local East-North-Up coordinates to ECEF given a reference point.

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How to use this calculator

Inputs

Rotate local east/north/up offsets at an origin into Earth-centred coordinates — or check an ECEF target back into ENU.

Origin

Decimal degrees (−31.95), DMS (31 57 0 S) or DDM (31° 57.0′ S).

Decimal degrees (115.86), DMS (115 51 36 E) or DDM (115° 51.6′ E).

Ellipsoidal height h — not AHD or sea level.

Local offsets
Ellipsoid

A shape only — choosing one does not transform between datums or epochs.

More options

Printed with the result so the numbers never travel without their reference. It is a label only: nothing is transformed.

Enter the values and press Calculate.

Or load an example to see a worked result.

East, north and up offsets at the origin
Not to scale
East, north and up offsets at the originOblique sketch of the east, north and up axes at the origin with the displacement vector and its three components.E (east)N (north)U (up)OriginENUTarget = origin + R·[E, N, U]
East, north and up axes at the origin; the local displacement is rotated into ECEF and added to the origin.

Batch from CSV

One row per calculation, with a header row. Values use the units currently selected in the form above. Up to 10,000 rows; nothing is uploaded.

How the method works

A fixed worked example to explain the method — it is not your result.

A local displacement is rotated, then added to the origin
Illustrative method
A local displacement is rotated, then added to the originOblique sketch of the east, north and up axes at the origin with the displacement vector and its three components.E (east)N (north)U (up)OriginENUTarget = origin + R·[E, N, U]
East, north and up axes at the origin; the local displacement is rotated into ECEF and added to the origin.

Before you rely on this: First-pass guide only. Verify safety-critical or regulated work against the relevant standards, your project requirements and a qualified professional.

How to use this calculator

  1. Choose the direction: ENU offsets → ECEF target, or ECEF target → ENU offsets.
  2. Enter the origin latitude, longitude and ellipsoidal height, and choose the ellipsoid.
  3. Enter East, North and Up in metres (negative values allowed), or the target X, Y, Z in reverse mode.
  4. Press Calculate. The rotated offset (ΔX, ΔY, ΔZ), the target and the vector length are shown separately.

How it works

The origin is converted to ECEF with the shared geodetic kernel.

R has rows [−sin λ, −sin φ cos λ, cos φ cos λ], [cos λ, −sin φ sin λ, cos φ sin λ], [0, cos φ, sin φ]; target = origin + R · [E, N, U].

Reverse mode uses the transpose: [E, N, U] = Rᵀ · (target − origin). R is orthonormal, so the vector length is unchanged by the rotation.

The frame is fixed at the origin. It is not rebuilt at each target, so for large offsets E and N are vector components, not grid or geodesic distances.

Worked example

Origin −31.95°, 115.86°, 50 m; E 100, N 200, U 5 m. The rotated offset is ΔX −138.000, ΔY 55.438, ΔZ 167.056 m (length 223.663 m), so the target is X −2,362,906.761, Y 4,874,643.593, Z −3,355,587.707 m. Reverse mode returns E 100, N 200, U 5 to within a micrometre.

Common mistakes

  • Mixing up the order E, N, U — a north offset entered as east rotates to a completely different target.
  • Using the ENU vector as a ground distance over many kilometres. The plane touches the ellipsoid only at the origin.
  • At a pole, assuming 'north' is unique. There the origin longitude you enter declares which way the local frame faces.

Frequently asked questions

What is ENU used for?

Local site grids, robotics, drones and target tracking use East-North-Up coordinates around a known origin.

Related tools

Explore more in Surveying, Coordinates, GIS & CAD.

Cite this tool

Zerdly. (2026). ENU (East/North/Up) to ECEF Converter. Retrieved from https://www.zerdly.com/tools/enu-east-north-up-to-ecef-converter/

Tip: Enter any known values to calculate the remaining results.

Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.