Make a choropleth map

This example map shows a choropleth map depicting state population data for the United States.

Read the documentation.

TypeScript

async function initMap() {
    // Request needed libraries.
    const { Map } = await google.maps.importLibrary("maps") as google.maps.MapsLibrary;

    const map = new Map(document.getElementById('map') as HTMLElement, {
        center: { lat: 40.76, lng: -101.64 },
        zoom: 5,
        // In the cloud console, configure this Map ID with a style that enables the
        // "Administrative Area Level 1" feature layer.
        mapId: '7ba16be0c9375fa7',
    });

    const featureLayer = map.getFeatureLayer(google.maps.FeatureType.ADMINISTRATIVE_AREA_LEVEL_1);

    featureLayer.style = featureStyleFunctionOptions => {
        const placeFeature = featureStyleFunctionOptions.feature as google.maps.PlaceFeature;
        const population = states[placeFeature.placeId];

        let fillColor;
        // Specify colors using any of the following:
        // * Named ('green')
        // * Hexadecimal ('#FF0000')
        // * RGB ('rgb(0, 0, 255)')
        // * HSL ('hsl(60, 100%, 50%)')

        if (population < 2000000) {
            fillColor = 'green'
        } else if (population < 5000000) {
            fillColor = 'red'
        } else if (population < 10000000) {
            fillColor = 'blue'
        } else if (population < 40000000) {
            fillColor = 'yellow'
        }
        return {
            fillColor,
            fillOpacity: 0.5
        }
    }
    // Population data by state.
    const states = {
        "ChIJdf5LHzR_hogR6czIUzU0VV4": 5039877, // Alabama
        "ChIJG8CuwJzfAFQRNduKqSde27w": 732673, // Alaska
        "ChIJaxhMy-sIK4cRcc3Bf7EnOUI": 7276316, // Arizona
        "ChIJYSc_dD-e0ocR0NLf_z5pBaQ": 3025891, // Arkansas
        "ChIJPV4oX_65j4ARVW8IJ6IJUYs": 39237836, // California
        "ChIJt1YYm3QUQIcR_6eQSTGDVMc": 5812069, // Colorado
        "ChIJpVER8hFT5okR5XBhBVttmq4": 3605597, // Connecticut
        "ChIJO9YMTXYFx4kReOgEjBItHZQ": 1003384, // Delaware
        "ChIJvypWkWV2wYgR0E7HW9MTLvc": 21781128, // Florida
        "ChIJV4FfHcU28YgR5xBP7BC8hGY": 10799566, // Georgia
        "ChIJBeB5Twbb_3sRKIbMdNKCd0s": 1441553, // Hawaii
        "ChIJ6Znkhaj_WFMRWIf3FQUwa9A": 1900923, // Idaho
        "ChIJGSZubzgtC4gRVlkRZFCCFX8": 12671469, // Illinois
        "ChIJHRv42bxQa4gRcuwyy84vEH4": 6805985, // Indiana
        "ChIJGWD48W9e7ocR2VnHV0pj78Y": 3193079, // Iowa
        "ChIJawF8cXEXo4cRXwk-S6m0wmg": 2934582, // Kansas
        "ChIJyVMZi0xzQogR_N_MxU5vH3c": 4509394, // Kentucky
        "ChIJZYIRslSkIIYRA0flgTL3Vck": 4624047, // Louisiana
        "ChIJ1YpTHd4dsEwR0KggZ2_MedY": 1372247, // Maine
        "ChIJ35Dx6etNtokRsfZVdmU3r_I": 6165129, // Maryland
        "ChIJ_b9z6W1l44kRHA2DVTbQxkU": 6984723, // Massachussetts
        "ChIJEQTKxz2qTE0Rs8liellI3Zc": 10050811, // Michigan
        "ChIJmwt4YJpbWE0RD6L-EJvJogI": 5707390, // Minnesota
        "ChIJGdRK5OQyKIYR2qbc6X8XDWI": 2949965, // Mississippi
        "ChIJfeMiSNXmwIcRcr1mBFnEW7U": 6168187, // Misssouri
        "ChIJ04p7LZwrQVMRGGwqz1jWcfU": 1104271, // Montana
        "ChIJ7fwMtciNk4cRxArzDwyQJ6E": 1963692, // Nebraska
        "ChIJcbTe-KEKmYARs5X8qooDR88": 3143991, // Nevada
        "ChIJ66bAnUtEs0wR64CmJa8CyNc": 1388992, // New Hampshire
        "ChIJn0AAnpX7wIkRjW0_-Ad70iw": 9267130, // New Jersey
        "ChIJqVKY50NQGIcRup41Yxpuv0Y": 2115877, // New Mexico
        "ChIJqaUj8fBLzEwRZ5UY3sHGz90": 19835913, // New York
        "ChIJgRo4_MQfVIgRGa4i6fUwP60": 10551162, // North Carolina
        "ChIJY-nYVxKD11IRyc9egzmahA0": 774948, // North Dakota
        "ChIJwY5NtXrpNogRFtmfnDlkzeU": 11780017, // Ohio
        "ChIJnU-ssRE5rIcRSOoKQDPPHF0": 3986639, // Oklahoma
        "ChIJVWqfm3xuk1QRdrgLettlTH0": 4246155, // Oregon
        "ChIJieUyHiaALYgRPbQiUEchRsI": 12964056, // Pennsylvania
        "ChIJD9cOYhQ15IkR5wbB57wYTh4": 1095610, // Rhode Island
        "ChIJ49ExeWml-IgRnhcF9TKh_7k": 5190705, // South Carolina
        "ChIJpTjphS1DfYcRt6SGMSnW8Ac": 895376, // South Dakota
        "ChIJA8-XniNLYYgRVpGBpcEgPgM": 6975218, // Tennessee
        "ChIJSTKCCzZwQIYRPN4IGI8c6xY": 29527941, // Texas
        "ChIJzfkTj8drTIcRP0bXbKVK370": 3337975, // Utah
        "ChIJ_87aSGzctEwRtGtUNnSJTSY": 645570, // Vermont
        "ChIJzbK8vXDWTIgRlaZGt0lBTsA": 8642274, // Virginia
        "ChIJ-bDD5__lhVQRuvNfbGh4QpQ": 7738692, // Washington
        "ChIJRQnL1KVUSogRQzrN3mjHALs": 1782959, // West Virginia
        "ChIJr-OEkw_0qFIR1kmG-LjV1fI": 5895908, // Wisconsin
        "ChIJaS7hSDTiXocRLzh90nkisCY": 578803, // Wyoming
    };
}

initMap();

JavaScript

async function initMap() {
  // Request needed libraries.
  const { Map } = await google.maps.importLibrary("maps");
  const map = new Map(document.getElementById("map"), {
    center: { lat: 40.76, lng: -101.64 },
    zoom: 5,
    // In the cloud console, configure this Map ID with a style that enables the
    // "Administrative Area Level 1" feature layer.
    mapId: "7ba16be0c9375fa7",
  });
  const featureLayer = map.getFeatureLayer(
    google.maps.FeatureType.ADMINISTRATIVE_AREA_LEVEL_1,
  );

  featureLayer.style = (featureStyleFunctionOptions) => {
    const placeFeature = featureStyleFunctionOptions.feature;
    const population = states[placeFeature.placeId];
    let fillColor;

    // Specify colors using any of the following:
    // * Named ('green')
    // * Hexadecimal ('#FF0000')
    // * RGB ('rgb(0, 0, 255)')
    // * HSL ('hsl(60, 100%, 50%)')
    if (population < 2000000) {
      fillColor = "green";
    } else if (population < 5000000) {
      fillColor = "red";
    } else if (population < 10000000) {
      fillColor = "blue";
    } else if (population < 40000000) {
      fillColor = "yellow";
    }
    return {
      fillColor,
      fillOpacity: 0.5,
    };
  };

  // Population data by state.
  const states = {
    "ChIJdf5LHzR_hogR6czIUzU0VV4": 5039877,
    "ChIJG8CuwJzfAFQRNduKqSde27w": 732673,
    "ChIJaxhMy-sIK4cRcc3Bf7EnOUI": 7276316,
    "ChIJYSc_dD-e0ocR0NLf_z5pBaQ": 3025891,
    "ChIJPV4oX_65j4ARVW8IJ6IJUYs": 39237836,
    "ChIJt1YYm3QUQIcR_6eQSTGDVMc": 5812069,
    "ChIJpVER8hFT5okR5XBhBVttmq4": 3605597,
    "ChIJO9YMTXYFx4kReOgEjBItHZQ": 1003384,
    "ChIJvypWkWV2wYgR0E7HW9MTLvc": 21781128,
    "ChIJV4FfHcU28YgR5xBP7BC8hGY": 10799566,
    "ChIJBeB5Twbb_3sRKIbMdNKCd0s": 1441553,
    "ChIJ6Znkhaj_WFMRWIf3FQUwa9A": 1900923,
    "ChIJGSZubzgtC4gRVlkRZFCCFX8": 12671469,
    "ChIJHRv42bxQa4gRcuwyy84vEH4": 6805985,
    "ChIJGWD48W9e7ocR2VnHV0pj78Y": 3193079,
    "ChIJawF8cXEXo4cRXwk-S6m0wmg": 2934582,
    "ChIJyVMZi0xzQogR_N_MxU5vH3c": 4509394,
    "ChIJZYIRslSkIIYRA0flgTL3Vck": 4624047,
    "ChIJ1YpTHd4dsEwR0KggZ2_MedY": 1372247,
    "ChIJ35Dx6etNtokRsfZVdmU3r_I": 6165129,
    "ChIJ_b9z6W1l44kRHA2DVTbQxkU": 6984723,
    "ChIJEQTKxz2qTE0Rs8liellI3Zc": 10050811,
    "ChIJmwt4YJpbWE0RD6L-EJvJogI": 5707390,
    "ChIJGdRK5OQyKIYR2qbc6X8XDWI": 2949965,
    "ChIJfeMiSNXmwIcRcr1mBFnEW7U": 6168187,
    "ChIJ04p7LZwrQVMRGGwqz1jWcfU": 1104271,
    "ChIJ7fwMtciNk4cRxArzDwyQJ6E": 1963692,
    "ChIJcbTe-KEKmYARs5X8qooDR88": 3143991,
    "ChIJ66bAnUtEs0wR64CmJa8CyNc": 1388992,
    "ChIJn0AAnpX7wIkRjW0_-Ad70iw": 9267130,
    "ChIJqVKY50NQGIcRup41Yxpuv0Y": 2115877,
    "ChIJqaUj8fBLzEwRZ5UY3sHGz90": 19835913,
    "ChIJgRo4_MQfVIgRGa4i6fUwP60": 10551162,
    "ChIJY-nYVxKD11IRyc9egzmahA0": 774948,
    "ChIJwY5NtXrpNogRFtmfnDlkzeU": 11780017,
    "ChIJnU-ssRE5rIcRSOoKQDPPHF0": 3986639,
    "ChIJVWqfm3xuk1QRdrgLettlTH0": 4246155,
    "ChIJieUyHiaALYgRPbQiUEchRsI": 12964056,
    "ChIJD9cOYhQ15IkR5wbB57wYTh4": 1095610,
    "ChIJ49ExeWml-IgRnhcF9TKh_7k": 5190705,
    "ChIJpTjphS1DfYcRt6SGMSnW8Ac": 895376,
    "ChIJA8-XniNLYYgRVpGBpcEgPgM": 6975218,
    "ChIJSTKCCzZwQIYRPN4IGI8c6xY": 29527941,
    "ChIJzfkTj8drTIcRP0bXbKVK370": 3337975,
    "ChIJ_87aSGzctEwRtGtUNnSJTSY": 645570,
    "ChIJzbK8vXDWTIgRlaZGt0lBTsA": 8642274,
    "ChIJ-bDD5__lhVQRuvNfbGh4QpQ": 7738692,
    "ChIJRQnL1KVUSogRQzrN3mjHALs": 1782959,
    "ChIJr-OEkw_0qFIR1kmG-LjV1fI": 5895908,
    "ChIJaS7hSDTiXocRLzh90nkisCY": 578803, // Wyoming
  };
}

initMap();

CSS

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

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

HTML

<html>
  <head>
    <title>Choropleth Map</title>
    <script src="https://polyfill.io/v3/polyfill.min.js?features=default"></script>

    <link rel="stylesheet" type="text/css" href="./style.css" />
    <script type="module" src="./index.js"></script>
  </head>
  <body>
    <div id="map"></div>

    <!-- prettier-ignore -->
    <script>(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: "AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg", v: "weekly"});</script>
  </body>
</html>

Try Sample

Clone Sample

Git and Node.js are required to run this sample locally. Follow these instructions to install Node.js and NPM. The following commands clone, install dependencies and start the sample application.

  git clone -b sample-boundaries-choropleth https://github.com/googlemaps/js-samples.git
  cd js-samples
  npm i
  npm start

Other samples can be tried by switching to any branch beginning with sample-SAMPLE_NAME.

  git checkout sample-SAMPLE_NAME
  npm i
  npm start