Secure contextThis feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
The GeolocationCoordinates
interface's read-only longitude
property is a double-precision floating point value which represents the longitude of a geographical position, specified in decimal degrees. Together with a DOMTimeStamp
indicating a time of measurement, the GeolocationCoordinates
object is part of the GeolocationPosition
interface, which is the object type returned by Geolocation API functions that obtain and return a geographical position.
Syntax
let longitude = geolocationCoordinatesInstance.longitude
Value
The value in longitude
is the geographical longitude of the location on Earth described by the Coordinates
object, in decimal degrees. The value is defined by the World Geodetic System 1984 specification (WGS 84).
Note: The zero meridian (also known as the prime meridian or the reference meridian) is not precisely the same as the Greenwhich meridian that most people think of. It is, instead, the IERS Reference Meridian, which is located 5.3 arcseconds (102 meters / 335 feet) east of the Greenwich meridian. This is the same standard used by the Global Positioning System (GPS).
Examples
In this simple example, we fetch the user's location and display the resulting coordinates once they're returned.
JavaScript
The JavaScript code below creates an event listener so that when the user clicks on a button, the location information is retrieved and displayed.
let button = document.getElementById("get-location");
let latText = document.getElementById("latitude");
let longText = document.getElementById("longitude");
button.addEventListener("click", function() {
navigator.geolocation.getCurrentPosition(function(position) {
let lat = position.coords.latitude;
let long = position.coords.longitude;
latText.innerText = lat.toFixed(2);
longText.innerText = long.toFixed(2);
});
});
After setting up variables to more conveniently reference the button element and the two elements into which the latitude and logitude will be drawn, the event listener is established by calling addEventListener()
on the <button>
element. When the user clicks the button, we'll fetch and display the location information.
Upon receiving a click
event, we call getCurrentPosition()
to request the device's current position. This is an asynchronous request, so we provide a callback which receives as in put a GeolocationPosition
object describing the determined position.
From the GeolocationPosition
object, we obtain the user's latitude and longitude using position.coords.latitude
and position.coords.longitude
so we can update the displayed coordinates. The two <span>
elements are updated to display the corresponding values after being converted to a value with two decimal places.
HTML
The HTML used to present the results looks like this:
<p>
Your location is <span id="latitude">0.00</span>°
latitude by <span id="longitude">0.00</span>° longitude.
</p>
<button id="get-location">
Get My Location
</button>
Result
Take this example for a test drive here:
Specifications
Specification | Status | Comment |
---|---|---|
Geolocation APIThe definition of 'Coordinates.longitude' in that specification. | Recommendation | Initial specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
longitude
|
Chrome
Full support 5 |
Edge
Full support 12 |
Firefox
Full support 3.5 |
IE
Full support 9 |
Opera Full support 16 Full support 16 No support 10.6 — 15 |
Safari
Full support 5 |
WebView Android
Full support 37 |
Chrome Android
Full support 18 |
Firefox Android
Full support 4 |
Opera Android Full support 16 Full support 16 No support 11 — 14 |
Safari iOS
? |
Samsung Internet Android
Full support 1.0 |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
See also
- Using the Geolocation API
- The
GeolocationCoordinates
interface it belongs to. - The
GeolocationPosition
interface, which is the top-level interface used to return geolocation data from the Geolocation API functionsGeolocation.getCurrentPosition()
andwatchPosition()
.
GeolocationCoordinates.longitude by Mozilla Contributors is licensed under CC-BY-SA 2.5.