Wikipedia:Obtaining geographic coordinates

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Obtaining[edit]

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.

From maps[edit]

From printed maps[edit]

Looking at a printed map or atlas, either those you own or at a library.

From online maps[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.

Tool Type Metadata types Coordinate parameters Description Licensing
GeoLocator
(project page)
Google Maps based {{coord}}, {{location}}, {{location dec}}, microformats, custom editable template type, scale, region, heading Coordinate picker and online metadata authoring tool.
Features: visual heading (camera direction) picker, GeoTemplate/GeoHack compatibility, flexible coordinate parser, URL integration, configurable degree/arcsec precision. Metadata roundtrip support – pasting of existing geotag, updating its location or parameters and encoding new one.
Coordinates tool Google Maps based {{Coor title dms (NL)}}, {{Coördinaten (NL)}}, {{Location (Commons)}}, {{Object location (Commons)}}, {{Coord (EN))}}, {{Infobox decimaal}}, {{Infobox)}} type, scale, region Coordinate picker and online metadata authoring tool.
Features: GeoTemplate/GeoHack compatibility.

Generic web-based services[edit]

These services are web based, and provide online methods for obtaining coordinates.

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

Tool Type Description Licensing
3maps Address to map Allows to paste the URL from many popular online mapping tools and get the current place and coordinates. Can search coordinates from a raw paragraph of text. The smart address search.
Alder's Koord-ermittlungs-Tool Map to coordinates A crosshair symbol will be placed in the centre of a Google Earth window. Place the cross hair exactly over the place and click on it. Then follow the link to specification.

The tool comes in two variants, one for en.wikipedia and Wikimedia Commons and one for de.wikipedia.

itouchmap Map to coordinates Move a marker on a Google Maps map (map or satellite view) and get Latitude, Longitude for the location. User interface in English language.
Mapcoordinates Map to coordinates Move a marker on a Google Maps map (map or satellite view) and get Latitude, Longitude and Elevation for the location. User interface in German language.
NASA World Wind Maps Open source 3D interactive world viewer. See also: online version

Licensing: NOSA

Bing Maps Maps Provides geographical coordinates of a location when a "Pushpin" has been created.
  1. Find the feature or the location you want to know the geographical coordinates of, either by manually using the map and zooming in, or by entering a place name or address into the search field.
  2. Right-click on the map at the site where you want the pushpin to appear.
  3. A pop-up tab will appear. Select Add a Pushpin and save it.
  4. Several icons are found to the lower left of the map, including a star for "My Places" and also an email icon. Click the Star to open "My Places".
  5. Select the most recent place which you have just saved.
  6. Click the email icon. The geographical coordinates are embedded in the email link which is then displayed. The coordinates are the two numbers displayed immediately after the letters "cp=". The latitude and longitude are separated by a tilde ( ~ ). The latitude is displayed first, and both coordinates are displayed in decimal degrees format. (in degrees only).
  • Alternatively, any of the locations in My Places can be exported either as a KML file or GPX file, both of which embed the coordinates. Export is done by clicking the Actions tab at the top of the My Places box.
  • The degrees-only geographical coordinates can be entered into Wikipedia's {{coord}} template. In the preview, click on the template and you will get to the Map sources page. There, the degrees-only geographical coordinates are converted into degrees-minutes-seconds anyway and displayed automatically at the top of the page, so you can still decide if you want to convert the degrees-only-geographical coordinates into the degree-minutes-seconds-format (alternatively, you can also use the website http://id.mind.net/~zona/mmts/trigonometryRealms/degMinSec/degMinSec.htm for the conversion from degrees-only into degree-minutes-seconds).

Licensing: Proprietary EULA

WikiMapia Global browser The latitude and longitude of the crosshairs are given at the bottom left of the screen and are constantly updated as the map is moved. Clicking on them will bring up a dialog box from which they can be copied in decimal or deg/min/sec form.

Licensing: Arieal imagery provided is from Google Earth Terms of use and one can switch to Bing Maps and OpenStreetMap as needed

Calculators Conversion Many scientific calculators (including the one that comes with Windows, use dms and inv dms) can convert coordinates.
The Getty Thesaurus of Geographic Names Name search Allows you to find coordinates with a place name search.

Licensing: [1]

Geonet Names Server (GNS) Name search U.S. National Geospatial-Intelligence Agency (NGA) maintains a comprehensive database of non-U.S. place data.
The Libre Map Project The purpose of the project is to aggregate and make digital maps and related GIS data available for free.

Licensing: CC-BY-SA 2.0

GPSies.com Google Maps tool Gives coordinates for places, names, elevation/height above sea level on Google Maps (reverse geocoding). You can download the coordinate as GPX Waypoint, PCX5 Waypoint, LOC Geocache or Google Earth KML.
GeocodeFarm Address & coordinate search Look up address by coordinates or coordinates by address. Forward and Reverse Geocoding Service. Web Form or API Available. API is free for 2,500 queries per day, more are paid. Web Form is free for unlimited queries. International Coverage in most countries.

Licensing: [2]

Great Circle Mapper Name search Has geographic coordinates for airports, heliports, and other facilities which have an IATA or ICAO code. You can also search by location name.
JRC Fuzzy Gazetteer Fuzzy name search Spelling tolerant place name gazetteer, mostly based on GSN data, enriched with data collected from United Nations missions and European Commission services.
Plexscape WS Google Maps tool – Coordinate converter Online application to acquire coordinates for any place on Earth.
  • Supports more than 3,000 coordinate systems and 400 datums worldwide.
  • Place pushpins on the map and calculates automatically the coordinates in the selected coordinate system or datum.
  • Perform transformation between coordinate systems and/or datums.
  • Extended units list available for calculations (meters, feet etc.)

Google Maps[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.
  • 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 any of the following bookmarklets (create a new bookmark with this code as the URL):
    • The following bookmarklet will create an output such as {{coord|51.5030515|-0.1281352}}:

      javascript: (function () { var matches = location.toString().match("\/maps\/.*@([0-9.-]+),([0-9.-]+)"); prompt('',"{{coord|" + matches[1] + "|" + matches[2] + "}}"); }());

    • The following bookmarklet will create an output such as {{coord|51|30|10.99|N|0|07|41.29|W|display=title}}:

      javascript:var matches = location.toString().match("\/maps\/.*@([0-9.-]+),([0-9.-]+)");coord=[matches[1],matches[2]];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));

To use these bookmarklets, centre the map on the desired point and then open the newly created bookmark. A coordinate template text will appear, ready to be pasted to Wikipedia.

Google Earth[edit]

Google Earth makes it easy to search for the coordinates of any location and zooming in on them. The coordinate format can be chosen via Tools → Options → 3D View → Show Lat/Long. There are many ways to obtain coordinates:

  • Move the mouse pointer to where you want, then use the keyboard to select the Menue item Edit → Copy View Location to copy the coordinates to the clipboard. More convenient is the associated keyboard shortcut. If it is not provided in the currently chosen language of Google Earth, change it to English (UK) (Tools → Options → General → Language settings).
  • Move the mouse pointer to where you want, and note the coordinates displayed on the bottom of the earth display window. 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.
  • Center the screen on your location by double-clicking on it, then use the View in Google Maps button at the top (Google Earth 4.1 and newer). This will open Google Maps within Google Earth. You can see the center coordinates in decimal format in the address bar, but unfortunately you cannot copy them directly. To do so, use the button Open this page in your default web browser to display the same Google Maps page in your browser with unrestricted access to its address bar. Of course, all the methods listed above for Google Maps are also available.
  • Center the screen on your location by double-clicking on it, then create a placemark (Add Placemark-button or Menu Add → Placemark. The "New Placemark" window displays the coordinates.
  • For the coordinates of an existing placemark, right click on it on the sidebar and select "Copy". This makes the clipboard hold a KML ("Keyhole Markup Language") description of the placemark. 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 lon/lat; you may want to swap the both in order to get the more common lat/lon notation. 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 exported kml or kmz file can also be converted to templates using the kmlconvert tool.

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 Airportworldwind://goto/world=Earth&lat=32.11611&lon=-110.94109&alt=24389"

From directories/databases[edit]

For the US[edit]

For other regions[edit]


From other sources[edit]

Formats and formatting[edit]

  • UK places and Irish places traditionally use grid references, and a latitude /longitude system tied to an OSGB36 datum. This gives a 112m difference.
  • The NAD83 map datum is sufficiently close to WGS84 for initial use. It is best to double check on a mapping site such as WikiMapia.
  • Cordinates obtained in China from commercial sources (Google, Bing, Baidu, etc.) may be obfuscated with GCJ-02 or BD-09. Vector sources are more frequently affected than satellite sources. Use this gadget to obtain deobfuscated coordinates, then double check on OpenStreetMap.

Add to article[edit]

Finally, add the coordinates to the relevant article:

Quick how to
To add 57°18′22″N 4°27′32″W / 57.30611°N 4.45889°W / 57.30611; -4.45889 to the top of an article, use {{Coord}}, thus:
{{Coord|57|18|22|N|4|27|32|W|display=title}}

These coordinates are in degrees, minutes, and seconds of arc.

"title" means that the coordinates will be displayed next to the article's title at the top of the page and before any other text or images.

To add 44°06′43″N 87°54′47″W / 44.112°N 87.913°W / 44.112; -87.913 to the top of an article, use either
{{Coord|44.112|N|87.913|W|display=title}}

(which does not require minutes or seconds but does require the user to specify north/ south and east/west) or

{{Coord|44.112|-87.913|display=title}}

(in which the north and east are presumed by positive values while the south and west are negative ones) These coordinates are in decimal degrees.

  • Degrees, minutes and seconds, when used, must each be separated by a pipe ("|").
  • Map datum must be WGS84 (except for off-earth bodies).
  • Avoid excessive precision (0.0001° is <11 m, 1″ is <31 m).
  • Maintain consistency of decimal places or minutes/ seconds between latitude and longitude.
  • Latitude (N/S) must appear before longitude (E/W).
Optional coordinate parameters follow the longitude and are separated by an underscore ("_"):

Other optional parameters are separated by a pipe ("|"):

  • display
    |display=inline (the default) to display in the body of the article only,
    |display=title to display at the top of the article only, or
    |display=inline,title to display in both places.
  • name
    name=X to label the place on maps (default is PAGENAME)

Thus: {{Coord|44.117|-87.913|dim:30_region:US-WI_type:event

|display=inline,title|name=accident site}}

Use |display=title (or |display=inline,title) once per article, for the subject of the article, where appropriate.

See also[edit]