diff --git a/firebase-installations/firebase-installations.gradle b/firebase-installations/firebase-installations.gradle
index 39b289c0834..0ef070e8b6d 100644
--- a/firebase-installations/firebase-installations.gradle
+++ b/firebase-installations/firebase-installations.gradle
@@ -52,6 +52,8 @@ dependencies {
     testImplementation 'androidx.test:core:1.2.0'
     testImplementation 'junit:junit:4.12'
     testImplementation "org.robolectric:robolectric:$robolectricVersion"
+    testImplementation "com.google.truth:truth:$googleTruthVersion"
+
 
     androidTestImplementation 'androidx.test.ext:junit:1.1.1'
     androidTestImplementation 'androidx.test:runner:1.2.0'
diff --git a/firebase-installations/src/main/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClient.java b/firebase-installations/src/main/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClient.java
index 51cc1869fae..e1a6facd6f5 100644
--- a/firebase-installations/src/main/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClient.java
+++ b/firebase-installations/src/main/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClient.java
@@ -15,6 +15,7 @@
 package com.google.firebase.installations.remote;
 
 import static android.content.ContentValues.TAG;
+import static com.google.android.gms.common.internal.Preconditions.checkArgument;
 
 import android.content.Context;
 import android.content.pm.PackageManager;
@@ -23,12 +24,13 @@
 import androidx.annotation.NonNull;
 import com.google.android.gms.common.util.AndroidUtilsLight;
 import com.google.android.gms.common.util.Hex;
+import com.google.android.gms.common.util.VisibleForTesting;
 import com.google.firebase.installations.InstallationTokenResult;
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.net.URL;
 import java.nio.charset.Charset;
-import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
 import java.util.zip.GZIPOutputStream;
 import javax.net.ssl.HttpsURLConnection;
 import org.json.JSONException;
@@ -61,6 +63,11 @@ public class FirebaseInstallationServiceClient {
 
   private static final int NETWORK_TIMEOUT_MILLIS = 10000;
 
+  private static final Pattern EXPIRATION_TIMESTAMP_PATTERN = Pattern.compile("[0-9]+s");
+
+  @VisibleForTesting
+  static final String PARSING_EXPIRATION_TIME_ERROR_MESSAGE = "Invalid Expiration Timestamp.";
+
   private final Context context;
 
   public FirebaseInstallationServiceClient(@NonNull Context context) {
@@ -273,7 +280,7 @@ private InstallationResponse readCreateResponse(HttpsURLConnection conn) throws
             installationTokenResult.setToken(reader.nextString());
           } else if (key.equals("expiresIn")) {
             installationTokenResult.setTokenExpirationInSecs(
-                TimeUnit.MILLISECONDS.toSeconds(reader.nextLong()));
+                parseTokenExpirationTimestamp(reader.nextString()));
           } else {
             reader.skipValue();
           }
@@ -301,7 +308,7 @@ private InstallationTokenResult readGenerateAuthTokenResponse(HttpsURLConnection
       if (name.equals("token")) {
         builder.setToken(reader.nextString());
       } else if (name.equals("expiresIn")) {
-        builder.setTokenExpirationInSecs(TimeUnit.MILLISECONDS.toSeconds(reader.nextLong()));
+        builder.setTokenExpirationInSecs(parseTokenExpirationTimestamp(reader.nextString()));
       } else {
         reader.skipValue();
       }
@@ -329,4 +336,19 @@ private String getFingerprintHashForPackage() {
       return null;
     }
   }
+
+  /**
+   * Returns parsed token expiration timestamp in seconds.
+   *
+   * @param expiresIn is expiration timestamp in String format: 604800s
+   */
+  @VisibleForTesting
+  static long parseTokenExpirationTimestamp(String expiresIn) {
+    checkArgument(
+        EXPIRATION_TIMESTAMP_PATTERN.matcher(expiresIn).matches(),
+        PARSING_EXPIRATION_TIME_ERROR_MESSAGE);
+    return (expiresIn == null || expiresIn.length() == 0)
+        ? 0L
+        : Long.parseLong(expiresIn.substring(0, expiresIn.length() - 1));
+  }
 }
diff --git a/firebase-installations/src/test/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClientTest.java b/firebase-installations/src/test/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClientTest.java
new file mode 100644
index 00000000000..eb30312c0e4
--- /dev/null
+++ b/firebase-installations/src/test/java/com/google/firebase/installations/remote/FirebaseInstallationServiceClientTest.java
@@ -0,0 +1,55 @@
+// Copyright 2019 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.firebase.installations.remote;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.common.truth.Truth.assertWithMessage;
+import static org.junit.Assert.fail;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.RobolectricTestRunner;
+
+/** Tests for {@link FirebaseInstallationServiceClient}. */
+@RunWith(RobolectricTestRunner.class)
+public class FirebaseInstallationServiceClientTest {
+
+  private final String TEST_EXPIRATION_TIMESTAMP = "604800s";
+  private final long TEST_EXPIRATION_IN_SECS = 604800;
+  private final String INCORRECT_EXPIRATION_TIMESTAMP = "2345";
+
+  @Test
+  public void parseTokenExpirationTimestamp_successful() {
+    long actual =
+        FirebaseInstallationServiceClient.parseTokenExpirationTimestamp(TEST_EXPIRATION_TIMESTAMP);
+
+    assertWithMessage("Exception status doesn't match")
+        .that(actual)
+        .isEqualTo(TEST_EXPIRATION_IN_SECS);
+  }
+
+  @Test
+  public void parseTokenExpirationTimestamp_failed() {
+    try {
+      FirebaseInstallationServiceClient.parseTokenExpirationTimestamp(
+          INCORRECT_EXPIRATION_TIMESTAMP);
+      fail("Parsing token expiration timestamp failed.");
+    } catch (IllegalArgumentException expected) {
+      assertThat(expected)
+          .hasMessageThat()
+          .isEqualTo(FirebaseInstallationServiceClient.PARSING_EXPIRATION_TIME_ERROR_MESSAGE);
+    }
+  }
+}