DMS ↔ Decimal Degrees Converter

Understanding DMS and Decimal Degrees

Geographic coordinates can be expressed in two common formats. DMS (Degrees, Minutes, Seconds) is the classical notation inherited from astronomy and nautical charts. Each degree is divided into 60 minutes and each minute into 60 seconds, producing values such as 41°00'29.5"N, 28°58'42.2"E. Handheld GPS receivers, paper topographic maps, aviation charts, and maritime instruments typically display coordinates in this form because it mirrors the traditional division of a circle.

Decimal degrees compress the same information into a single floating-point number per axis — for example 41.008194, 28.978389. The conversion formula is straightforward: decimal = degrees + minutes/60 + seconds/3600. For southern latitudes or western longitudes the sign is negative, so 33°30'00"S becomes −33.5. Hemisphere can be signalled either with a trailing letter (N, S, E, W) or a leading minus sign — both are accepted here.

Mapping software, spatial databases, web APIs, and formats such as GeoJSON and WKT all use decimal degrees as their native coordinate representation because the format is compact and directly usable in arithmetic. ArcGIS, for example, stores feature geometries in decimal degrees when the spatial reference is WGS 84.

• DMS use cases: nautical charts, aviation waypoints, military mapping, legacy GPS devices, and printed survey data
• Decimal degree use cases: web mapping APIs, GeoJSON, PostGIS, ArcGIS REST services, and any programmatic coordinate handling
• Bidirectional conversion: this tool converts DMS → decimal and decimal → DMS with equal accuracy
• Batch conversion: paste an entire list of coordinate pairs — one per line — to process many points in a single operation without manual re-entry

How to Use This Tool

To convert DMS to decimal degrees, type or paste your DMS latitude into the left "Latitude" field (e.g. 41°00'29.5"N) and your DMS longitude into the left "Longitude" field, then click DMS → Decimal. The equivalent decimal values appear immediately in the right-hand fields, and a map pin is plotted so you can visually confirm the location.

To convert in the opposite direction, enter decimal degree values in the right-hand fields and click Decimal → DMS. The tool reconstructs degrees, minutes, and seconds with a hemisphere letter appended. For batch conversion, paste one coordinate pair per line into the batch input area, using a comma, semicolon, or tab as the separator between latitude and longitude. Space-separated DMS such as 41 0 29.5 N is supported in batch mode; just avoid placing a comma inside the DMS value itself since the comma is interpreted as the field delimiter. Click Batch Convert → Decimal to process all rows at once and copy the results.

Other Coordinate Tools

If you need to reproject coordinates between different coordinate reference systems or EPSG codes, our Coordinate Converter handles a wide range of CRS transformations. For converting GPS track or waypoint files between common exchange formats, the GPS Converter is the right starting point.