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Coordinate Converter

Convert GPS coordinates between Decimal Degrees, DMS, and DDM formats instantly.

Coordinate Converter

Enter coordinates in any format, see all conversions instantly

Decimal Degrees (DD)
40.712800, -74.006000
Degrees Minutes Seconds (DMS)
40°42′46.1″N 74°0′21.6″W
Degrees Decimal Minutes (DDM)
40°42.768′N 74°0.360′W
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Understanding Coordinate Formats

Geographic coordinates identify any location on Earth using two numbers: latitude (north-south position, -90 to +90) and longitude (east-west position, -180 to +180). The same location can be expressed in multiple formats:

  • Decimal Degrees (DD) — The simplest format: 40.7128, -74.0060. Used by most digital mapping systems, APIs, and databases. Negative values indicate South (latitude) or West (longitude).
  • Degrees Minutes Seconds (DMS) — The traditional format: 40°42′46.1″N 74°0′21.6″W. Used in aviation, nautical charts, and printed maps. One degree = 60 minutes, one minute = 60 seconds.
  • Degrees Decimal Minutes (DDM) — A hybrid format: 40°42.768′N 74°0.360′W. Popular in marine GPS units and geocaching. Combines the readability of DMS with the precision of decimals.

Conversion Formulas

DD to DMS: Degrees = integer part. Minutes = integer of (decimal × 60). Seconds = remainder × 60.

DMS to DD: DD = Degrees + Minutes/60 + Seconds/3600

DD to DDM: Degrees = integer part. Decimal Minutes = decimal part × 60.

GPS and Coordinate Systems

The Global Positioning System (GPS) uses the WGS 84 (World Geodetic System 1984) coordinate reference system, which defines the shape of the Earth as an ellipsoid. All three coordinate formats (DD, DMS, DDM) can express WGS 84 coordinates — they are simply different ways to write the same numbers.

GPS accuracy depends on the number of decimal places. In Decimal Degrees: 4 decimal places give ~11 meter accuracy, 5 decimal places give ~1.1 meter accuracy, and 6 decimal places give ~0.11 meter accuracy. For most practical purposes, 6 decimal places are more than sufficient.

Different applications prefer different formats. Google Maps and most web APIs use DD. Aviation (ICAO standards) uses DMS. Marine navigation and geocaching typically use DDM. This converter lets you switch between all three seamlessly.