There are various ways to obtain geographic coordinates. Note that regardless of the source of coordinates, it is a good practice to evaluate whether they appear reasonable at first glance.

Manually[edit]

• Using a GPS receiver with a clear view of the sky.
• Looking at a printed map or atlas, either those you own or at a library.

Public domain databases[edit]

• U.S. Board on Geographic Names – The United States Geological Survey public domain GNIS database contains a huge list of locations in the United States. It can be found on the Web at geonames.usgs.gov. Most of these coordinates use the NAD83 map datum, which is sufficiently close to WGS84 for use.
• US Census TIGER
• US Census Boundary and Annexation Survey

On the web[edit]

Wikipedia compatible geotagging metadata generators[edit]

List of services, directly providing Wikipedia/Wikimedia Commons compatible geotagging metadata.

Currently preferred geotagging templates are: {{coord...}} for English Wikipedia and {{location...}} or {{location dec..}} for Wikimedia Commons.

Generic web based services[edit]

These services are web based, and provide on-line methods for obtaining co-ordinates.

Be sure to read the licensing information carefully so that data providers receive an appropriate attribution.

Coordinates also can be found in other sources, such as:

• Looking at a website built by GPS users, e.g., geourl.org, www.findu.com or www.geocaching.com
• Looking for GPS "Waypoint" files
• Looking at a wiki that uses map coordinates, e.g., susning.nu

Google tools[edit]

• Google Maps can be used to find coordinates 3 different ways, although many other sites make use of Google imagery with specialist overlays.
  • The simplest way to get coordinates from Google Maps is to right-click on the desired location and click "What's here?". The coordinates are now shown in the search box.
  • Another method is using the LatLng ToolTip from Google Maps. This feature is activated through Google Labs by entering its Google Maps Labs section here. The Tool Tip will display a box with coordinates that move as the mouse cursor is moved. Note that the upper left corner of the tooltip box actually becomes the precise point of the cursor whose coordinates are displayed in the box. There is also a related LatLng Marker tool which is useful because it makes it easy to copy and paste the coordinates.
  • Coordinates can also be extracted from generated links with the following procedure. First locate the place you require coordinates for, and double click on it to centre the map around that point. Then click "Link" at the top of the map, and the coordinates (in degrees and parts of a degree in decimals) appear in the address bar, e.g. "http://maps.google.co.uk/?ll=51.455558,-2.605047&spn=0.032304,0.069523". In this case the latitude is 51.455558, and the longitude is -2.605047. The reverse is possible by entering the lat and long into the search bar, with a space between them. Based on Google Maps API and geocoder, this page simplifies the task by displaying directly the coordinates, including in one of Wikipedia formats (for English and French Wikipedias), and allowing quick finding of places either by moving the map or typing in postal addresses or place names. Informal research indicates that coordinates obtained in this way usually agree with precisely determined WGS84 coordinates to within about ten meters, or four decimal places in decimal degree notation.
  • Copying the coordinates from the URL can be made easier with a Javascript-supporting browser, by adding the following bookmarklet (create a new bookmark with this code as the URL):

    javascript:void(prompt('',"{{coord|" + gApplication.getMap().getCenter().lat() + "|" + gApplication.getMap().getCenter().lng() + "}}"));

    Centre the map on the point as previously, and then open the newly created bookmark. A coordinate template text will appear, ready to be pasted to Wikipedia. Alternatively, to format the coordinates directly into the template code for articles, with display next to the title, use the following code as a bookmarklet:
    

Caution: a previous version of this code was faulty. If you installed this Bookmarklet before June 15. 2009 please update it with the current version..

javascript:coord=[gApplication.getMap().getCenter().lat(),gApplication.getMap().getCenter().lng()];output='{{coord|';for(x in [0,1]){neg=(coord[x]<0);coord[x]=Math.abs(coord[x]);deg=Math.floor(coord[x]);minr=(coord[x]-deg)*60;min=Math.floor(minr);sec=Math.floor((minr - min)*60*100000)/100000;output+=deg+"|"+(min<10?'0':'')+min+"|"+(sec<10?'0':'')+sec.toFixed(2)+'|'+(x==0?(neg?'S|':'N|'):(neg?'W|':'E|')+"display=title}}");};void(prompt('Coordinates for Wikipedia',output));

• Googling for the city name together with "latitude", "longitude", which will give hits like http://www.infoplease.com/ipa/A0001769.html
• Google Earth makes it easy to search for the coordinates of any location and zooming in on them. There are many ways to obtain coordinates:
  • Move the mouse cursor to where you want, and note the coordinates displayed in the lower left-hand corner of the earth display window. The display format can be changed in the Options. The numbers will have to be written from the screen manually, but this does let you choose an appropriately rounded value, without excess precision, for the location you're capturing.
  • Google Earth 4.1 and newer can make a Google Maps URL, from which you can copy the latitude and longitude in decimal format as mentioned above. Just center the screen on your location by double-clicking on it, and then use the "View in Google Maps" button at the top.
  • Create a placemark (probably in the "Temporary Places" folder). Right-click or control-click on the placemark; one of the options is "Copy". Copy the placemark and paste it back to a text editor. The result is a KML ("Keyhole Markup Language") description of the placemark, and since KML is XML, it's easily manipulable. Towards the bottom of the placemark is a tag <coordinates>...</coordinates> which contains the long/lat coordinates in decimal degrees. Note that the order of the coordinates is reversed from the lat/long you were expecting; you have to swap them when you extract them. Also note that the precision is ridiculously high; you'll probably want to trim it down.
  • Install the Google Earth version of the hjl_get_Coor tool: Ald-Hjl-Koord-en.kmz. Once it's installed, a crosshair icon appears in the middle of the Google Earth screen. Move the view so that the crosshair is on your desired location, and then click on it. There is a link to the hjl_get_Coor tool, which gives the coordinates back in your chosen wiki markup that can be copied and pasted to an article.
  • The Picasa application allows seamless integration with Google Earth to tag sets of images saved on the computer. Select the images to tag on Picasa, and then choose "Tools / Geotag / Geotag With Google Earth". Google Earth opens with first of the chosen images in the bottom right corner, and a crosshair in the middle of the screen. Move the view so that the crosshair is on top of the desired location, and click on the Geotag button. A placemark will be added to your Temporary Places folder, from where you can normally copy it in kml format as explained above. Clicking Done will return to Picasa, which can export the data in kmz at any later date.[5] [6]
  • The exported kml or kmz file can also be converted to templates using the kmlconvert tool.
• Various Google-based tools can be used to find latitude and longitude coordinates, such as the following: [7], [8], and [9].

OpenStreetMap[edit]

OpenStreetMap can be used; simply navigate to the desired point by double-clicking on it, select the "share" icon from the top-left toolbar, copy the "link" URL (N.B. not the shortlink) and extract the coordinate values from it.

For example, http://www.openstreetmap.org/?lat=52.54341&lon=-1.91035&zoom=15&layers=M includes a latitude of 52.54341 and a longitude of -1.91035.

World Wind[edit]

NASA World Wind can access a large online database of U.S. and global placenames (cities, villages and other geographic & anthropogenic features). Street addresses can be found using Yahoo and Virtual Earth geocoders (works for the US, Australia, UK, Japan... and maybe some other countries). (Offline search requires this pack http://www.worldwindcentral.com/wiki/Add-on:Classic_Placenames_cache_pack) Press Ctrl-F, enter the official place name, click Search, you will probably find the place you're looking for. Click Go. (of course you can navigate to the desired spot with your mouse; select View->Show Position to see the coordinates) Press Ctrl-C to copy the decimal coordinates. Paste it into Wikipedia. Example: For Tucson International Airport → worldwind://goto/world=Earth&lat=32.11611&lon=-110.94109&alt=24389"

Within Wikipedia[edit]

• Category:Lists of coordinates
• CatScan in the example with buildings in New York City with or without Coordinates.

Specific countries/places[edit]

• PlaceNames provides coordinates for locations and landmarks in the United States.
• For US coordinates, the USGS GNIS service is extremely extensive. It also provides linkouts to topozone and terraserver so that you can tweak the results to your liking.
• For US addresses, A2B provides you with the latitude and longitude of a US street address and returns nearest websites to that address. You can then add your own sites.
• Find Longitude and Latitude coordinates by US Zip Code
• For placenames in Antarctica, try Geographic Names Information System, Antarctica
• For Australian placenames, try Geoscience Australia Place Name Search
• For Canadian places Canadian Geographical Names Data Base (CGNDB) Querying Canadian Geographical Names
• For UK places, Streetmap.co.uk is very useful for clicking on a precise point to show the coordinates. Near the foot of a page displaying a map is a link "Click here to convert/measure coordinates" which takes you to a "Grid Conversion Results" page with the WGS84 latitude and longitude amongst other useful values.
• UK places and Irish places traditionally use grid references, and a latitude /longitude system tied to an OSGB36 datum. This gives a 112m difference. OStoWiki Tool will translate data from Commons tags, or Grid References into Wikipedia tags. Wikipedia's own output from GeoHack is broken: it does not take the different datum into account, and therefore returns Grid References which are wrong by about 100m. Note that List of United Kingdom locations already has coordinates and grid references for many places.
• Display UK Longitude and Latitude

Add to article[edit]

Finally, add the coordinates to the relevant article:

See also[edit]

• Geographic coordinate system
• List of geographic information systems software
• List of GIS data sources
• Wikipedia:WikiProject Geographical coordinates