diff --git a/jaxtyping/_array_types.py b/jaxtyping/_array_types.py
index d8d0a19..d77c496 100644
--- a/jaxtyping/_array_types.py
+++ b/jaxtyping/_array_types.py
@@ -224,12 +224,12 @@ def _check_shape(
         arg_memo: dict[str, Any],
     ) -> str:
         if cls.index_variadic is None:
-            if obj.ndim != len(cls.dims):
-                return f"this array has {obj.ndim} dimensions, not the {len(cls.dims)} expected by the type hint"  # noqa: E501
+            if len(obj.shape) != len(cls.dims):
+                return f"this array has {len(obj.shape)} dimensions, not the {len(cls.dims)} expected by the type hint"  # noqa: E501
             return _check_dims(cls.dims, obj.shape, single_memo, arg_memo)
         else:
-            if obj.ndim < len(cls.dims) - 1:
-                return f"this array has {obj.ndim} dimensions, which is fewer than {len(cls.dims) - 1} that is the minimum expected by the type hint"  # noqa: E501
+            if len(obj.shape) < len(cls.dims) - 1:
+                return f"this array has {len(obj.shape)} dimensions, which is fewer than {len(cls.dims) - 1} that is the minimum expected by the type hint"  # noqa: E501
             i = cls.index_variadic
             j = -(len(cls.dims) - i - 1)
             if j == 0: