Elevation requests and responses

Elevation requests

Elevation API requests are constructed as a URL string. The API returns elevation data for locations on the earth. You specify location data in one of two ways:

  • As a set of one or more locations.
  • As a series of connected points along a path.

Either of these approachs uses latitude/longitude coordinates to identify the locations or path vertices. This document describes the required format of Elevation API URLs and the available parameters.

The Elevation API returns data for single point queries of the highest accuracy possible. Batch queries involving multiple locations may return data with less accuracy, especially if the locations are spread apart, as some smoothing of data occurs.

A Elevation API request takes the following form:

https://maps.googleapis.com/maps/api/elevation/outputFormat?parameters

where outputFormat may be either of the following values:

  • json (recommended), indicates output in JavaScript Object Notation (JSON); or
  • xml, indicates output in XML, wrapped within a <ElevationResponse> node.

Note: URLs must be properly encoded to be valid and are limited to 16384 characters for all web services. Be aware of this limit when constructing your URLs. Note that different browsers, proxies, and servers may have different URL character limits as well.

HTTPS is required for requests that use an API key.

Request parameters

Requests to the Elevation API utilize different parameters based on whether the request is for discrete locations or for an ordered path. For discrete locations, requests for elevation return data on the specific locations passed in the request; for paths, elevation requests are instead sampled along the given path.

As is standard in all URLs, parameters are separated using the ampersand (&amp;) character. The list of parameters and their possible values are denoted below.

All requests

  • key — (required) Your application's API key. This key identifies your application for purposes of quota management. Learn how to get a key.

Positional requests

  • locations (required) defines the location(s) on the earth from which to return elevation data. This parameter takes either a single location as a comma-separated {latitude,longitude} pair (e.g. "40.714728,-73.998672") or multiple latitude/longitude pairs passed as an array or as an encoded polyline. There is a 512 point limit for this specific parameter. For more information, see Specifying Locations below.

Sampled path requests

  • path (required) defines a path on the earth for which to return elevation data. This parameter defines a set of two or more ordered {latitude,longitude} pairs defining a path along the surface of the earth. This parameter must be used in conjunction with the samples parameter described below. There is a 512 point limit for this specific parameter. For more information, see Specifying Paths below.
  • samples (required) specifies the number of sample points along a path for which to return elevation data. The samples parameter divides the given path into an ordered set of equidistant points along the path.

Specifying locations

Positional requests are indicated through use of the locations parameter, indicating elevation requests for the specific locations passed as latitude/longitude values.

The locations parameter may take the following arguments:

  • A single coordinate: locations=40.714728,-73.998672
  • An array of coordinates separated using the pipe ('|') character: locations=40.714728,-73.998672|-34.397,150.644
  • A set of encoded coordinates using the Encoded Polyline Algorithm: locations=enc:gfo}EtohhU

Latitude and longitude coordinate strings are defined using numerals within a comma-separated text string. For example, "40.714728,-73.998672" is a valid locations value. Latitude and longitude values must correspond to a valid location on the face of the earth. Latitudes can take any value between -90 and 90 while longitude values can take any value between -180 and 180. If you specify an invalid latitude or longitude value, your request will be rejected as a bad request.

You may pass up to 512 coordinates within an array or encoded polyline, while still constructing a valid URL. Note that when passing multiple coordinates, the accuracy of any returned data may be of lower resolution than when requesting data for a single coordinate. Exceeding 512 points or coordinates in the 'locations' or 'path' parameters returns an INVALID_REQUEST response.

Specifying paths

Sampled path requests are indicated through use of the path and samples parameters, indicating a request for elevation data along a path at specified intervals. As with positional requests using the locations parameter, the path parameter specifies a set of latitude and longitude values. Unlike a positional request, however, the path specifies an ordered set of vertices. Rather than return elevation data only at the vertices, path requests are sampled along the length of the path, based on the number of samples specified (inclusive of the endpoints).

The path parameter may take either of the following arguments:

  • An array of two or more comma-separated coordinate text strings separated using the pipe ('|') character: path=40.714728,-73.998672|-34.397,150.644
  • Encoded coordinates using the Encoded Polyline Algorithm: path=enc:gfo}EtohhUxD@bAxJmGF

Latitude and longitude coordinate strings are defined using numerals within a comma-separated text string. For example, "40.714728,-73.998672|-34.397, 150.644" is a valid path value. Latitude and longitude values must correspond to a valid location on the face of the earth. Latitudes can take any value between -90 and 90 while longitude values can take any value between -180 and 180. If you specify an invalid latitude or longitude value, your request will be rejected as a bad request.

You may pass up to 512 coordinates within an array or encoded polyline, while still constructing a valid URL. Note that when passing multiple coordinates, the accuracy of any returned data may be of lower resolution than when requesting data for a single coordinate. Exceeding 512 points or coordinates in the 'locations' or 'path' parameters returns an INVALID_REQUEST response.

Elevation responses

For each valid request, the Elevation service will return an Elevation response in the format indicated within the request URL.

ElevationResponse

FieldRequiredTypeDescription
required Array<ElevationResult> See ElevationResult for more information.
requiredElevationStatus See ElevationStatus for more information.
optionalstring

When the service returns a status code other than OK, there may be an additional error_message field within the response object. This field contains more detailed information about thereasons behind the given status code. This field is not always returned, and its content is subject to change.

ElevationStatus

Status codes returned by service.

  • OK indicating the API request was successful.
  • DATA_NOT_AVAILABLE indicating that there's no available data for the input locations.
  • INVALID_REQUEST indicating the API request was malformed.
  • OVER_DAILY_LIMIT indicating any of the following:
    • The API key is missing or invalid.
    • Billing has not been enabled on your account.
    • A self-imposed usage cap has been exceeded.
    • The provided method of payment is no longer valid (for example, a credit card has expired).
  • OVER_QUERY_LIMIT indicating the requestor has exceeded quota.
  • REQUEST_DENIED indicating the API did not complete the request.
  • UNKNOWN_ERROR indicating an unknown error.

When the status code is other than OK, there may be an additional error_message field within the Elevation response object. This field contains more detailed information about the reasons behind the given status code.

The response contains a results array with the following elements:

ElevationResult

FieldRequiredTypeDescription
requirednumber

The elevation of the location in meters.

requiredLatLngLiteral

A location element of the position for which elevation data is being computed. Note that for path requests, the set of location elements will contain the sampled points along the path.

See LatLngLiteral for more information.

optionalnumber

The value indicating the maximum distance between data points from which the elevation was interpolated, in meters. This property will be missing if the resolution is not known. Note that elevation data becomes more coarse (larger resolution values) when multiple points are passed. To obtain the most accurate elevation value for a point, it should be queried independently.

The location object has the following elements:

LatLngLiteral

An object describing a specific location with Latitude and Longitude in decimal degrees.

FieldRequiredTypeDescription
requirednumber

Latitude in decimal degrees

requirednumber

Longitude in decimal degrees

Positional elevation examples

The following example requests the elevation for Denver, Colorado, the "Mile High City" in the JSON format:

URL

https://maps.googleapis.com/maps/api/elevation/json
  ?locations=39.7391536%2C-104.9847034
  &key=YOUR_API_KEY

cURL

curl -L -X GET 'https://maps.googleapis.com/maps/api/elevation/json?locations=39.7391536%2C-104.9847034&key=YOUR_API_KEY'

JSON

{
  "results":
    [
      {
        "elevation": 1608.637939453125,
        "location": { "lat": 39.7391536, "lng": -104.9847034 },
        "resolution": 4.771975994110107,
      },
    ],
  "status": "OK",
}

XML

<ElevationResponse>
 <status>OK</status>
 <result>
  <location>
   <lat>39.7391536</lat>
   <lng>-104.9847034</lng>
  </location>
  <elevation>1608.6379395</elevation>
  <resolution>4.7719760</resolution>
 </result>
</ElevationResponse>

The following example shows multiple responses (for Denver, CO and for Death Valley, CA).

This request demonstrates using the JSON output flag:

URL

https://maps.googleapis.com/maps/api/elevation/json
  ?locations=39.7391536%2C-104.9847034%7C36.455556%2C-116.866667
  &key=YOUR_API_KEY

cURL

curl -L -X GET 'https://maps.googleapis.com/maps/api/elevation/json?locations=39.7391536%2C-104.9847034%7C36.455556%2C-116.866667&key=YOUR_API_KEY'

This request demonstrates using the XML output flag:

https://maps.googleapis.com/maps/api/elevation/xml?locations=39.7391536,-104.9847034|36.455556,-116.866667&key=YOUR_API_KEY

Select the tabs below to see the sample JSON and XML responses.

JSON

{
  "results":
    [
      {
        "elevation": 1608.637939453125,
        "location": { "lat": 39.7391536, "lng": -104.9847034 },
        "resolution": 4.771975994110107,
      },
      {
        "elevation": -52.79492568969727,
        "location": { "lat": 36.455556, "lng": -116.866667 },
        "resolution": 19.08790397644043,
      },
    ],
  "status": "OK",
}

XML

<ElevationResponse>
 <status>OK</status>
 <result>
  <location>
   <lat>39.7391536</lat>
   <lng>-104.9847034</lng>
  </location>
  <elevation>1608.6379395</elevation>
  <resolution>4.7719760</resolution>
 </result>
 <result>
  <location>
   <lat>36.4555560</lat>
   <lng>-116.8666670</lng>
  </location>
  <elevation>-52.7949257</elevation>
  <resolution>19.0879040</resolution>
 </result>
</ElevationResponse>

The following examples requests elevation data along a straight line path from Mt. Whitney, CA to Badwater, CA, the highest and lowest points in the continental United States. We ask for three samples, so that will include the two endpoints and the halfway point.

URL

https://maps.googleapis.com/maps/api/elevation/json
  ?path=36.578581%2C-118.291994%7C36.23998%2C-116.83171
  &samples=3
  &key=YOUR_API_KEY

cURL

curl -L -X GET 'https://maps.googleapis.com/maps/api/elevation/json?path=36.578581%2C-118.291994%7C36.23998%2C-116.83171&samples=3&key=YOUR_API_KEY'

JSON

{
  "results":
    [
      {
        "elevation": 4411.94189453125,
        "location": { "lat": 36.578581, "lng": -118.291994 },
        "resolution": 19.08790397644043,
      },
      {
        "elevation": 1372.8359375,
        "location": { "lat": 36.41150289067028, "lng": -117.5602607523847 },
        "resolution": 9.543951988220215,
      },
      {
        "elevation": -84.51690673828125,
        "location": { "lat": 36.23998, "lng": -116.83171 },
        "resolution": 9.543951988220215,
      },
    ],
  "status": "OK",
}

XML

<ElevationResponse>
 <status>OK</status>
 <result>
  <location>
   <lat>36.5785810</lat>
   <lng>-118.2919940</lng>
  </location>
  <elevation>4411.9418945</elevation>
  <resolution>19.0879040</resolution>
 </result>
 <result>
  <location>
   <lat>36.4115029</lat>
   <lng>-117.5602608</lng>
  </location>
  <elevation>1372.8359375</elevation>
  <resolution>9.5439520</resolution>
 </result>
 <result>
  <location>
   <lat>36.2399800</lat>
   <lng>-116.8317100</lng>
  </location>
  <elevation>-84.5169067</elevation>
  <resolution>9.5439520</resolution>
 </result>
</ElevationResponse>