diff --git a/include/fplus/split.hpp b/include/fplus/split.hpp
index 5543d963..f7b2a31d 100644
--- a/include/fplus/split.hpp
+++ b/include/fplus/split.hpp
@@ -713,7 +713,7 @@ Container stride(std::size_t step, const Container& xs)
 template <typename Container>
 Container winsorize(double trim_ratio, const Container& xs)
 {
-    if (size_of_cont(xs) < 2)
+    if (size_of_cont(xs) == 1 || size_of_cont(xs) == 0)
     {
         return xs;
     }
diff --git a/include_all_in_one/include/fplus/fplus.hpp b/include_all_in_one/include/fplus/fplus.hpp
index 93d833f6..b82ab013 100644
--- a/include_all_in_one/include/fplus/fplus.hpp
+++ b/include_all_in_one/include/fplus/fplus.hpp
@@ -11256,7 +11256,7 @@ Container stride(std::size_t step, const Container& xs)
 template <typename Container>
 Container winsorize(double trim_ratio, const Container& xs)
 {
-    if (size_of_cont(xs) < 2)
+    if (size_of_cont(xs) == 1 || size_of_cont(xs) == 0)
     {
         return xs;
     }