GPS Coordinate (DMS/DD), Haversine Distance & NMEA-0183 Generator (2026)

In NMEA-0183 sentences like $GPGGA and $GPRMC, latitude is represented as DDMM.MMMM (two digits of degrees followed immediately by decimal minutes) and longitude as DDDMM.MMMM. To convert NMEA 3746.4940,N to Decimal Degrees, divide the minutes (46.4940) by 60 and add to degrees (37 + 0.7749 = 37.7749°).

The NMEA checksum is computed by taking the bitwise exclusive OR (XOR) of the ASCII byte values of every character strictly between the starting '$' (or '!') and the terminating '*', formatted as a two-digit uppercase hexadecimal number.

Flat-plane Euclidean geometry ignores the curvature of the Earth and the convergence of longitude meridians toward the poles. The Haversine formula uses spherical trigonometry over Earth's mean radius (6,371.0088 km) to compute accurate great-circle surface distances.

Android's Location API sets the Location.isMock() flag when coordinates are injected via Settings > Developer Options > Select mock location app, or when sensor fusion detects zero accelerometer step cadence and static HDOP/altitude jitter during rapid coordinate changes.

A Geohash interleaves latitude and longitude bits into a base-32 string. A 5-character Geohash defines a bounding box of roughly 4.9 km × 4.9 km, a 7-character Geohash narrows to ~153 m × 153 m, and a 9-character Geohash pinpoints a ~4.77 m × 4.77 m square.