Geocoding is the process of converting addresses (like "366 West Circle Drive, East Lansing, MI 48824") into geographic coordinates (such as: latitude 42.731063, longitude -84.483278) which can then be used to place points representing the addresses on maps and create point shapefiles for use in GIS.
Things to remember when geocoding:
- Your addresses need to be correct and clear, your data must be clean. For more information about general formatting in geocoding, see this Best Practices guide from Harvard.
- You will need to do quality control. No geocoder is perfect!
- Most data needs to be in .csv format (just use Save As -> to convert your .xls to a .csv file) and will need to be formatted differently depending on the geocoder used.
- If you only have a few addresses it may be overkill to automate and batch process the geocoding. You can find coordinate information via Google Maps. Just right click on your result flag and choose “What’s Here?” Click on the Latitude/Longitude link and copy the result in the search box – not the degree/minute/second result (so this: 44.988834,-93.216097 NOT: 44°59'19.8"N 93°12'58.0"W). This lat/long can be copied into an excel spread sheet, where you can use the text to column tool to split the field into Latitude and Longitude fields and then import the sheet into ArcGIS or QGIS to create XY data points.