How to Read Longitude and Latitude

By Alan Li
Young student looking at a globe.

Longitude and latitude make up the most common and popular grid system used to navigate around the Earth. Longitude refers to the vertical lines called meridians that converge at the North and South Poles, using the Prime Meridian at Greenwich in England as the main reference. The Prime Meridian has a longitude of zero. In contrast, latitude refers to the horizontal lines that run around the circumference of the Earth, using the equator, also at zero degrees, as the main reference. Each line increases in number as the distance increases between the line and its reference. The distance between each line can be further divided into 60 minutes, and even further divided a second time into 60 seconds.

Read the longitude. Most longitude coordinates are expressed as degrees, minutes, seconds, and then the direction of the coordinate in relation to the Prime Meridian. For example, a longitude coordinate that reads 55° 20' 15'' W means that the coordinate lies 55 degrees, 20 minutes, and 15 seconds west of the Prime Meridian. Longitude maxes out at 180° east and 180° west.

Read the latitude. Latitude coordinates are expressed using the same formats as longitude coordinates. For example, a latitude coordinate 20° 45' 0'' N means that it is 20 degrees, 45 minutes, and 0 seconds north of the equator. It is important to keep in mind that latitude is limited to 90° north and 90° south of the equator.

Piece together the longitude and latitude coordinates to place the location on the imagined grid that overlies the surface of the Earth. You should use the longitude and latitude lines of the grid to help pinpoint the location of the coordinates. In some cases, the grid might not be detailed enough for you to find anything other than a general location of the coordinates.

Use an appropriate computing tool to conduct reverse geocoding if you are interested in finding the address of the location specified in the longitude and latitude coordinates. Free geocoding services are available via a number of websites, and using them is as simple as entering the longitude and latitude coordinates into the websites.


Another popular format for longitude and latitude coordinates is the decimal degrees format, which expresses the coordinates using positive and negative values. For reference, a positive coordinate means that the coordinate is located either north or east while a negative coordinate means that the coordinate is located either south or west.

About the Author

Alan Li started writing in 2008 and has seen his work published in newsletters written for the Cecil Street Community Centre in Toronto. He is a graduate of the finance program at the University of Toronto with a Bachelor of Commerce and has additional accreditation from the Canadian Securities Institute.