diff --git a/nc_time_axis/__init__.py b/nc_time_axis/__init__.py
index ccb8d87..ff0e52e 100644
--- a/nc_time_axis/__init__.py
+++ b/nc_time_axis/__init__.py
@@ -287,11 +287,11 @@ def convert(cls, value, unit, axis):
 
         ut = cftime.utime(cls.standard_unit, calendar=first_value.calendar)
 
-        if isinstance(value, (CalendarDateTime, cftime.datetime)):
-            value = [value]
-
         if isinstance(first_value, CalendarDateTime):
-            result = ut.date2num([v.datetime for v in value])
+            if isinstance(value, np.ndarray):
+                result = ut.date2num([v.datetime for v in value])
+            else:
+                result = ut.date2num(value.datetime)
         else:
             result = ut.date2num(value)
 
diff --git a/nc_time_axis/tests/unit/test_NetCDFTimeConverter.py b/nc_time_axis/tests/unit/test_NetCDFTimeConverter.py
index 5d5edaf..9bdad63 100644
--- a/nc_time_axis/tests/unit/test_NetCDFTimeConverter.py
+++ b/nc_time_axis/tests/unit/test_NetCDFTimeConverter.py
@@ -110,12 +110,16 @@ def test_numeric_iterable(self):
     def test_cftime_CalendarDateTime(self):
         val = CalendarDateTime(cftime.datetime(2014, 8, 12), '365_day')
         result = NetCDFTimeConverter().convert(val, None, None)
-        np.testing.assert_array_equal(result, 5333.)
+        expected = 5333.0
+        assert result == expected
+        assert np.isscalar(result)
 
     def test_cftime_raw_date(self):
         val = cftime.DatetimeNoLeap(2014, 8, 12)
         result = NetCDFTimeConverter().convert(val, None, None)
-        np.testing.assert_array_equal(result, 5333.)
+        expected = 5333.0
+        assert result == expected
+        assert np.isscalar(result)
 
     def test_cftime_np_array_CalendarDateTime(self):
         val = np.array([CalendarDateTime(cftime.datetime(2012, 6, 4),