Bearing to Azimuth Converter
Convert between compass bearing (-180° to 180°) and azimuth (0° to 360°). Edit either field to convert instantly.
Clockwise from North. Always positive.
Positive = East of North. Negative = West of North.
Quick examples
Azimuth vs Bearing — what is the difference?
Azimuth is always a positive angle measured clockwise from North, ranging from 0° to 360°. It is the standard in surveying and navigation.
Bearing ranges from -180° to 180°: positive values point East of North, negative values point West of North. This is the convention used in Turf.js, PostGIS, and many GIS libraries.
| Direction | Azimuth | Bearing |
|---|---|---|
| North | 0° | 0° |
| Northeast | 45° | 45° |
| East | 90° | 90° |
| Southeast | 135° | 135° |
| South | 180° | 180° |
| Southwest | 225° | -135° |
| West | 270° | -90° |
| Northwest | 315° | -45° |
Powered by Turf.js. All calculations run in your browser.
What is the difference between bearing and azimuth?
Bearing and azimuth both express a direction from north, but use different numeric conventions. Azimuth runs from 0° to 360° clockwise — north is 0°, east is 90°, south is 180°, west is 270°. Compass bearing uses the range −180° to 180°, where west is −90° and south is ±180°.
GIS software, spatial databases, and most navigation APIs use azimuth because it avoids the ±180° discontinuity of compass bearing and integrates more cleanly with mathematical operations. Traditional navigation instruments and some survey equipment use compass bearing notation.
Common use cases
GIS direction attribute conversion
Convert direction values from survey data (which may use compass bearing) to azimuth for storage in a GIS attribute table.
Navigation and routing
Convert azimuth headings from a GIS calculation to compass bearing for display on a compass or navigation app.
Wind and current data processing
Meteorological data often uses azimuth; oceanographic or aviation data may use bearing. Convert between conventions before combining datasets.
Antenna and satellite alignment
Convert between the azimuth values used by antenna alignment tools and the bearing values expected by a site survey instrument.
Frequently asked questions
What is the difference between bearing and azimuth?
Both express a direction from north, but with different conventions. Azimuth measures clockwise from north in the range 0° to 360° (north = 0°, east = 90°, south = 180°, west = 270°). Compass bearing also measures from north but uses the range −180° to 180° (or sometimes expressed as N/S + degrees + E/W, e.g., S45°E). GIS software commonly uses azimuth; navigation instruments often use bearing.
Why does GIS use azimuth instead of compass bearing?
Azimuth's 0°–360° range maps naturally to numeric operations and comparisons in GIS calculations. It avoids the discontinuity at ±180° that exists in the compass bearing convention and integrates more cleanly with trigonometric functions.
What is true north vs magnetic north?
True north points toward the geographic North Pole. Magnetic north points toward the magnetic pole, which differs from true north by the magnetic declination angle — this varies by location and changes over time. GIS coordinates always use true north; compass readings use magnetic north and require a declination correction for precision work.
How do I convert azimuth to bearing in code?
Bearing = azimuth > 180 ? azimuth − 360 : azimuth. For example: azimuth 270° → bearing −90° (due west). The reverse: azimuth = bearing < 0 ? bearing + 360 : bearing.