diff --git a/analytical/tests/test_tag_google_analytics_gtag.py b/analytical/tests/test_tag_google_analytics_gtag.py
new file mode 100644
index 0000000..723bc34
--- /dev/null
+++ b/analytical/tests/test_tag_google_analytics_gtag.py
@@ -0,0 +1,48 @@
+"""
+Tests for the Google Analytics template tags and filters, using the new gtag.js library.
+"""
+
+from django.http import HttpRequest
+from django.template import Context
+from django.test.utils import override_settings
+
+from analytical.templatetags.google_analytics_gtag import GoogleAnalyticsGTagNode
+from analytical.tests.utils import TagTestCase
+from analytical.utils import AnalyticalException
+
+
+@override_settings(GOOGLE_ANALYTICS_GTAG_PROPERTY_ID='UA-123456-7')
+class GoogleAnalyticsTagTestCase(TagTestCase):
+    """
+    Tests for the ``google_analytics_js`` template tag.
+    """
+
+    def test_tag(self):
+        r = self.render_tag('google_analytics_gtag', 'google_analytics_gtag')
+        self.assertTrue("""<script async src="https://www.googletagmanager.com/gtag/js?id=UA-123456-7"></script>""" in r, r)
+        self.assertTrue("gtag('js', new Date());" in r, r)
+        self.assertTrue("gtag('config', 'UA-123456-7');" in r, r)
+
+    def test_node(self):
+        r = GoogleAnalyticsGTagNode().render(Context())
+        self.assertTrue("""<script async src="https://www.googletagmanager.com/gtag/js?id=UA-123456-7"></script>""" in r, r)
+        self.assertTrue("gtag('js', new Date());" in r, r)
+        self.assertTrue("gtag('config', 'UA-123456-7');" in r, r)
+
+    @override_settings(GOOGLE_ANALYTICS_GTAG_PROPERTY_ID=None)
+    def test_no_property_id(self):
+        self.assertRaises(AnalyticalException, GoogleAnalyticsGTagNode)
+
+    @override_settings(GOOGLE_ANALYTICS_GTAG_PROPERTY_ID='wrong')
+    def test_wrong_property_id(self):
+        self.assertRaises(AnalyticalException, GoogleAnalyticsGTagNode)
+
+    @override_settings(ANALYTICAL_INTERNAL_IPS=['1.1.1.1'])
+    def test_render_internal_ip(self):
+        req = HttpRequest()
+        req.META['REMOTE_ADDR'] = '1.1.1.1'
+        context = Context({'request': req})
+        r = GoogleAnalyticsGTagNode().render(context)
+        self.assertTrue(r.startswith(
+            '<!-- Google Analytics disabled on internal IP address'), r)
+        self.assertTrue(r.endswith('-->'), r)