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>

        <link rel="stylesheet" type="text/css" href="./style.css" />
        <script type="module" src="./index.js"></script>
        <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))})({
                key: "GOOGLE_MAPS_API_KEY"
            });
        </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,
    });

    marker.anchorTop = '40px';

    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:...