diff --git a/src/nipanel/_convert.py b/src/nipanel/_convert.py
index 9488f54..54888d9 100644
--- a/src/nipanel/_convert.py
+++ b/src/nipanel/_convert.py
@@ -54,6 +54,12 @@
 
 def to_any(python_value: object) -> any_pb2.Any:
     """Convert a Python object to a protobuf Any."""
+    best_matching_type = _get_best_matching_type(python_value)
+    converter = _CONVERTER_FOR_PYTHON_TYPE[best_matching_type]
+    return converter.to_protobuf_any(python_value)
+
+
+def _get_best_matching_type(python_value: object) -> str:
     underlying_parents = type(python_value).mro()  # This covers enum.IntEnum and similar
 
     container_type = None
@@ -86,9 +92,7 @@ def to_any(python_value: object) -> any_pb2.Any:
             f"Unsupported type: ({container_type}, {payload_type}) with parents {underlying_parents}. Supported types are: {_SUPPORTED_PYTHON_TYPES}"
         )
     _logger.debug(f"Best matching type for '{repr(python_value)}' resolved to {best_matching_type}")
-
-    converter = _CONVERTER_FOR_PYTHON_TYPE[best_matching_type]
-    return converter.to_protobuf_any(python_value)
+    return best_matching_type
 
 
 def from_any(protobuf_any: any_pb2.Any) -> object:
diff --git a/tests/unit/test_convert.py b/tests/unit/test_convert.py
index a14a359..db97b2c 100644
--- a/tests/unit/test_convert.py
+++ b/tests/unit/test_convert.py
@@ -70,6 +70,51 @@ def test___python_panel_collection___to_any___valid_paneltype_value(
     assert unpack_dest.values == expected_value
 
 
+# ========================================================
+# _get_best_matching_type() tests
+# ========================================================
+@pytest.mark.parametrize(
+    "python_object, expected_type_string",
+    [
+        (False, "bool"),
+        (b"mystr", "bytes"),
+        (456.2, "float"),
+        (123, "int"),
+        ("mystr", "str"),
+        ([False, False], "Collection.bool"),
+        ([b"mystr", b"mystr"], "Collection.bytes"),
+        ([456.2, 1.0], "Collection.float"),
+        ([123, 456], "Collection.int"),
+        (["mystr", "mystr"], "Collection.str"),
+        ((False, False), "Collection.bool"),
+        ((b"mystr", b"mystr"), "Collection.bytes"),
+        ((456.2, 1.0), "Collection.float"),
+        ((123, 456), "Collection.int"),
+        (("mystr", "mystr"), "Collection.str"),
+        ((False, False), "Collection.bool"),
+        ((b"mystr", b"mystr"), "Collection.bytes"),
+        ((456.2, 1.0), "Collection.float"),
+        ((123, 456), "Collection.int"),
+        (("mystr", "mystr"), "Collection.str"),
+        (set([False, True]), "Collection.bool"),
+        (set([b"mystr", b"mystr2"]), "Collection.bytes"),
+        (set([456.2, 1.0]), "Collection.float"),
+        (set([123, 456]), "Collection.int"),
+        (set(["mystr", "mystr2"]), "Collection.str"),
+        (frozenset([False, True]), "Collection.bool"),
+        (frozenset([b"mystr", b"mystr2"]), "Collection.bytes"),
+        (frozenset([456.2, 1.0]), "Collection.float"),
+        (frozenset([123, 456]), "Collection.int"),
+        (frozenset(["mystr", "mystr2"]), "Collection.str"),
+    ],
+)
+def test___various_python_objects___get_best_matching_type___returns_correct_type_string(
+    python_object: object, expected_type_string: str
+) -> None:
+    type_string = nipanel._convert._get_best_matching_type(python_object)
+    assert type_string == expected_type_string
+
+
 # ========================================================
 # Protobuf to Python
 # ========================================================