ST_AZIMUTH()

All functions > GEOSPATIAL > ST_AZIMUTH()

Returns the azimuth angle in radians from point A to point B, measured clockwise from north (positive Y axis).

Signatures

Azimuth

Returns: Azimuth in radians in the range [0, 2π)

ST_AZIMUTH(geo1: T, geo2: T) → DOUBLE

With:

• T : Custom types: GEOM_POINT | GEOG_POINT

Signature notes:

• Returns angle in radians (not degrees), measured clockwise from the positive Y axis (north)
• Range is [0, 2π); due north = 0, due east = π/2 (~1.5708), due south = π, due west = 3π/2—users expecting compass degrees (e.g. 90° east) should multiply by 180.0 / PI()
• Returns NULL if either point is NULL or if both points are equal
• On GEOMETRY: planar azimuth in SRID coordinate units
• On GEOGRAPHY: initial bearing of the great circle arc from geo1 to geo2
• GEOGRAPHY overload: supported on DuckDB and BigQuery only; not supported on Trino or DataFusion

Examples

Geometry (planar)

SELECT
    f1 := ST_AZIMUTH(ST_GEOMPOINT(0.0, 0.0), ST_GEOMPOINT(0.0, 1.0)), -- Due north: azimuth is 0
    f2 := ST_AZIMUTH(ST_GEOMPOINT(0.0, 0.0), ST_GEOMPOINT(1.0, 0.0)) -- Due east: π/2 radians (not 90° unless converted)
;

Geography (geodesic)

SELECT
    f1 := ST_AZIMUTH(ST_GEOGPOINT(2.3522, 48.8566), ST_GEOGPOINT(2.3522, 51.5074)) -- Paris to London (same longitude): due north
;