Coordinate Format Converter
Convert GPS coordinates between Decimal Degrees, DMS, UTM, MGRS, Geohash, and Plus Codes. Professional geodesy calculator for surveyors, GIS, and developers.
Coordinate Systems Explained
Coordinate systems are frameworks for determining positions on Earth’s surface. Different systems are optimized for different purposes - from global navigation to precise surveying, military operations, and spatial databases.
Understanding Different Coordinate Formats
Decimal Degrees (DD)
Format: 40.7128, -74.0060
Use Cases: GPS devices, web mapping, mobile apps, databases
The most common format for digital applications. Simple, compact, and easy to process. Latitude ranges from -90 to 90, longitude from -180 to 180. Negative values indicate South and West.
Degrees Minutes Seconds (DMS)
Format: 40°42'46"N, 74°00'22"W
Use Cases: Traditional navigation, aviation, marine charts
Traditional format used in navigation for centuries. Each degree is divided into 60 minutes, and each minute into 60 seconds. More intuitive for manual calculations and map reading.
Universal Transverse Mercator (UTM)
Format: Zone 18N, 583960E, 4507523N
Use Cases: Surveying, engineering, topographic mapping, GIS
A metric coordinate system that divides the world into 60 zones, each 6° wide. Provides coordinates in meters (Easting/Northing), making distance calculations straightforward. Highly accurate within each zone. Used extensively in professional surveying and engineering.
Military Grid Reference System (MGRS)
Format: 18TWL8396007523
Use Cases: Military operations, emergency services, search and rescue
Based on UTM but uses a compact alphanumeric format. Adopted by NATO militaries worldwide. Designed for easy communication over radio and precision at various scales. The grid square letters help reduce errors in coordinate transmission.
Geohash
Format: dr5regw3pg6ft
Use Cases: Spatial databases, proximity searches, URL shortening
A hierarchical spatial indexing system that encodes coordinates into a short string. Longer strings = higher precision. Nearby locations share common prefixes, making it excellent for database queries and spatial indexing. Popular in NoSQL databases like Redis and MongoDB.
Plus Codes (Open Location Code)
Format: 87G8Q2J8+2V
Use Cases: Addressing places without street addresses, humanitarian aid
Developed by Google as a free, open-source alternative to street addresses. Works anywhere in the world, even in areas without formal addressing systems. Particularly valuable in developing countries, rural areas, and disaster zones.
Understanding Datums
What is a Datum and Why Does It Matter?
A datum is a reference framework that defines how coordinates relate to Earth’s actual surface. Since Earth isn’t a perfect sphere, different datums use different mathematical models (ellipsoids) to approximate its shape.
WGS84 (World Geodetic System 1984)
The global standard used by GPS satellites. Most modern applications use WGS84. Default choice for most users.
NAD83 (North American Datum 1983)
Used for surveying and mapping in North America. Very close to WGS84 but optimized for North American plate tectonics.
NAD27 (North American Datum 1927)
Legacy datum still found on older maps. Can differ from WGS84 by up to 200 meters. Important for historical data.
ED50 (European Datum 1950)
Historical European standard, now largely replaced by ETRS89. Still used in some legacy systems.
⚠️ Important: Using the wrong datum can result in position errors of up to several hundred meters. Always verify which datum your coordinates use!
UTM Zones Explained
The UTM system divides Earth into 60 zones, each covering 6° of longitude. Zones are numbered 1-60 starting at 180°W. Each zone uses a Transverse Mercator projection centered on the zone’s central meridian.
- Zones extend from 80°S to 84°N latitude
- Each zone has a central meridian with minimal distortion
- Distortion increases toward zone edges (±3° from center)
- Coordinates are in meters: Easting (0-834,000m), Northing (0-10,000,000m)
- False Easting of 500,000m prevents negative numbers
- Special zones exist for Norway (32V) and Svalbard (31X, 33X, 35X, 37X)
Real-World Use Cases
Surveying & Engineering
UTM coordinates provide meter-based measurements ideal for construction sites, property boundaries, and infrastructure projects. NAD83 is standard for North American surveying.
Military & Emergency Services
MGRS provides unambiguous location references for tactical operations, search and rescue, and disaster response. Compact format reduces communication errors.
Software Development
Geohash enables efficient spatial queries in databases. Decimal degrees work best for APIs and web services. Plus Codes provide URL-friendly location sharing.
Aviation & Marine Navigation
DMS format remains standard in aviation charts and marine navigation. Pilots and mariners use it for flight plans, waypoints, and position reporting.
Geocaching & Hiking
Recreational GPS users typically work with decimal degrees or DMS. UTM is popular for wilderness navigation and off-trail hiking where grid navigation is useful.
GIS & Mapping
GIS professionals work with all formats depending on project requirements. Coordinate transformation is essential when combining data from different sources.
Frequently Asked Questions
What’s the most accurate coordinate format?
All formats can represent positions with the same accuracy. The precision depends on the number of decimal places or digits used, not the format itself. UTM is often preferred for surveying because it uses meters, making distance calculations simpler.
Which datum should I use?
Use WGS84 for most modern applications, especially if you’re working with GPS data or web mapping. Use NAD83 for North American surveying and engineering. Always use the same datum as your data source.
How precise is a 6-character Geohash?
A 6-character Geohash covers approximately 1.2 km × 0.6 km (±0.61 km accuracy). Each additional character increases precision by ~5x. An 8-character Geohash is accurate to about ±19 meters, suitable for most location-based applications.
Can I use this converter for navigation?
This tool is designed for coordinate conversion and educational purposes. While the conversions are accurate, always verify coordinates with professional-grade tools for critical navigation, surveying, or safety-critical applications.
Why do my UTM coordinates look different from another source?
Different datums will produce different UTM coordinates for the same location. Also check if you’re using the correct UTM zone - coordinates near zone boundaries may be expressed in different zones. Some tools also round to different precisions.
What’s the difference between UTM and MGRS?
MGRS is based on UTM but uses an alphanumeric format that’s easier to communicate verbally. It adds grid zone designators and 100km grid square letters to UTM coordinates, making them more compact and less prone to transcription errors.
Precision Guide
Decimal Degree Precision
0.000001° (6 decimals): ~0.11 meters - GPS accuracy
0.00001° (5 decimals): ~1.1 meters - Building entrance accuracy
0.0001° (4 decimals): ~11 meters - Street address accuracy
0.001° (3 decimals): ~111 meters - Neighborhood accuracy
0.01° (2 decimals): ~1.1 km - Town accuracy
0.1° (1 decimal): ~11 km - City accuracy
Geohash Precision
12 characters: ~3.7 cm × 1.9 cm
11 characters: ~14.9 cm × 14.9 cm
10 characters: ~59.5 cm × 1.2 m
9 characters: ~4.8 m × 4.8 m - GPS accuracy
8 characters: ~19 m × 38 m - Address accuracy
7 characters: ~153 m × 153 m - Block accuracy
6 characters: ~610 m × 1.2 km - Neighborhood accuracy