diff --git a/tests/test_fernet.py b/tests/test_fernet.py
index 6558d11..75ecc35 100644
--- a/tests/test_fernet.py
+++ b/tests/test_fernet.py
@@ -122,6 +122,15 @@
         with pytest.raises(ValueError):
             Fernet(base64.urlsafe_b64encode(b"abc"), backend=backend)
 
+    def test_extract_timestamp(self, monkeypatch, backend):
+        f = Fernet(base64.urlsafe_b64encode(b"\x00" * 32), backend=backend)
+        current_time = 1526138327
+        monkeypatch.setattr(time, "time", lambda: current_time)
+        token = f.encrypt(b'encrypt me')
+        assert f.extract_timestamp(token) == current_time
+        with pytest.raises(InvalidToken):
+            f.extract_timestamp(b"nonsensetoken")
+
 
 @pytest.mark.requires_backend_interface(interface=CipherBackend)
 @pytest.mark.requires_backend_interface(interface=HMACBackend)