How to Convert GPS Coordinates Between DD, DMS and DDM

To convert GPS coordinates, paste a latitude and longitude in any format into a coordinate converter and read the result in decimal degrees, degrees-minutes-seconds, and decimal minutes at once. The parser understands values like 40.7128, 40°26'46"N, and 40°26.767'N, so you never have to reformat your input by hand.

The problem is that every tool speaks a different dialect. GPS units, GIS software, aviation charts, and web maps each prefer a different notation, and copying a value from one into another means either mental arithmetic or a fresh transcription error. A converter that shows all three formats side by side removes that friction entirely.

Why coordinate formats collide

Latitude and longitude can be written three common ways. Decimal degrees (DD) like 40.446111 are what web maps and GeoJSON expect. Degrees-minutes-seconds (DMS) like 40°26'46"N appear on legal land descriptions and older charts. Degrees decimal minutes (DDM) like 40°26.767'N is the default on aviation and marine GPS. Surveyors, drone pilots, geocachers, sailors, and developers all cross these boundaries constantly, and a reliable converter saves time while preventing costly mistakes.

How to convert coordinates in your browser

1. Type or paste a latitude into the Latitude field — decimal degrees, DMS, or DDM all parse correctly.
2. Enter the matching longitude in the Longitude field using whatever format you have.
3. Read the converted values instantly in all three formats at once.
4. Click Copy beside any format to put that version on your clipboard.

DD vs. DMS vs. DDM at a glance

Knowing which format goes where helps you avoid feeding the wrong notation into a system that cannot read it:

Format	Example	Where it is used
Decimal Degrees (DD)	40.446111, -79.982222	Web maps, GeoJSON, most APIs
Degrees-Minutes-Seconds (DMS)	40°26'46"N 79°58'56"W	Legal descriptions, paper charts
Degrees Decimal Minutes (DDM)	40°26.767'N 79°58.933'W	Aviation and marine GPS units

To go from DMS to DD by hand you divide the minutes by 60 and the seconds by 3600, then add both to the degrees; south and west values turn negative. This tool does that arithmetic the instant you paste a value, in either direction.

Key features and benefits

• Converts DD, DMS, and DDM together in a single view.
• A flexible parser that accepts 40°26'46"N, 40 26 46 N, and signed decimals.
• Range validation for latitude ±90° and longitude ±180°.
• One-click copy for every output format.
• 100% private — coordinates never leave your browser.
• Free, no sign-up, and works offline as a PWA.

Try the Coordinate Converter now — it's free and runs entirely in your browser.

Frequently asked questions

How do I convert DMS to decimal degrees?

Add the degrees to the minutes divided by 60 and the seconds divided by 3600. For 40°26'46"N that gives 40 + 26/60 + 46/3600 = 40.446111°, and south or west directions become negative. The converter performs this the moment you paste a value.

What is the difference between DMS and DDM?

DMS splits each degree into 60 minutes and each minute into 60 seconds, while DDM keeps whole degrees but writes the minutes as a decimal. DDM is standard on aviation and marine GPS units, whereas DMS is common on legal land records.

How many decimal places do GPS coordinates need?

Five decimal places locate a point to about 1.1 metres at the equator, and six to roughly 11 centimetres. Since consumer GPS is only accurate to a few metres, five or six decimals is more than enough for nearly every real-world task.

Why is my longitude negative?

In decimal degrees the sign encodes the hemisphere: negative longitude is west of Greenwich and negative latitude is south of the equator. That is why New York sits at roughly 40.7128, -74.0060.

Can I paste coordinates from Google Maps?

Yes. Google Maps copies decimal degrees like "40.712800, -74.006000", and pasting each number gives you the DMS and DDM equivalents at once. The parser also handles the DMS strings Google shows in search results.

Related free tools

• Latitude Longitude Finder — validate and map messy coordinate strings.
• Distance Calculator — measure the distance between two points.
• KML Circle Generator — draw radius circles for Google Earth.
• Unit Converter — convert distances, areas, and more.

Built by ByteVancer

ByteTools is a free product of ByteVancer, a software and web development studio that builds web apps, SaaS platforms, and custom software for businesses. If your team needs mapping, GIS, or data tooling built properly, explore ByteVancer's services or reach out about your project.