geocoding-reverse

Sample code supporting Google Maps Platform JavaScript API documentation. author(s): Geo Developer IX Documentation Team

HTML

<!doctype html>
<!--
@license
Copyright 2026 Google LLC. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0
-->

<html>
  <head>
    <title>Reverse Geocoding</title>

    <script>
      // prettier-ignore
      (g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})({
            });
    </script>
  </head>
  <body>
    <gmp-map center="0.714224, -73.961452" zoom="8" map-id="DEMO_MAP_ID">
      <div id="floating-panel" slot="control-block-start-inline-start">
        <p>Click the map to reverse geocode, or add your own coordinates.</p>
        <input id="latlng" type="text" value="40.714224, -73.961452" /><br />
        <input id="submit" type="button" value="Reverse Geocode" />
      </div>
    </gmp-map>
  </body>
</html>

CSS

/**
* @license
* Copyright 2026 Google LLC. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0
*/

/*
* Always set the map height explicitly to define the size of the div element
* that contains the map.
*/
gmp-map {
  height: 100%;
}

/*
* Optional: Makes the sample page fill the window.
*/
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
  font-family: Roboto, sans-serif;
}

#floating-panel {
  background-color: #fff;
  border-radius: 5px;
  box-shadow: rgba(0, 0, 0, 0.35) 0px 5px 15px;
  margin: 10px;
  padding: 10px;
  font-family: Roboto, sans-serif;
  font-size: 1rem;
}

#latlng {
  width: 100%;
  font-family: Roboto, sans-serif;
  font-size: 1rem;
  margin-bottom: 4px;
}

#submit {
  font-size: 1rem;
}

JavaScript

'use strict';
/**
 * @license
 * Copyright 2026 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

let marker;

async function init() {
  //  Request the needed libraries.
  const [{ InfoWindow }, { Geocoder }, { AdvancedMarkerElement }] =
    await Promise.all([
      google.maps.importLibrary('maps'),
      google.maps.importLibrary('geocoding'),
      google.maps.importLibrary('marker'),
    ]);

  // Get the gmp-map element.
  const mapElement = document.querySelector('gmp-map');

  // Get the inner map.
  const innerMap = mapElement.innerMap;

  // Get the latlng input box.
  const latLngQuery = document.getElementById('latlng');

  // Get the submit button.
  const submitButton = document.getElementById('submit');

  // Set the cursor to crosshair.
  innerMap.setOptions({
    draggableCursor: 'crosshair',
    zoom: 13,
    mapTypeControl: false,
  });

  // Create a marker for re-use.
  marker = new AdvancedMarkerElement({
    map: innerMap,
  });

  const geocoder = new Geocoder();
  const infoWindow = new InfoWindow();

  // Add a click event listener to the submit button.
  submitButton.addEventListener('click', () => {
    void geocodeLatLng(geocoder, innerMap, infoWindow);
  });

  // Add a click event listener to the map.
  innerMap.addListener('click', (event) => {
    if (event.latLng) {
      latLngQuery.value = `${event.latLng.lat()}, ${event.latLng.lng()}`;
      void geocodeLatLng(geocoder, innerMap, infoWindow);
    }
  });

  // Make an initial request upon loading.
  void geocodeLatLng(geocoder, innerMap, infoWindow);
}

async function geocodeLatLng(geocoder, map, infoWindow) {
  const input = document.getElementById('latlng').value;
  const latlngStr = input.split(',', 2);
  const latlng = {
    lat: parseFloat(latlngStr[0]),
    lng: parseFloat(latlngStr[1]),
  };

  try {
    const { results } = await geocoder.geocode({ location: latlng });

    if (results[0]) {
      marker.position = latlng;
     ...