diff --git a/src/calculator.py b/src/calculator.py
index e41739a..da4a182 100644
--- a/src/calculator.py
+++ b/src/calculator.py
@@ -6,3 +6,7 @@ def add(left: int, right: int) -> int:
 
 def subtract(left: int, right: int) -> int:
     return left - right
+
+
+def clamp_to_byte(value: int) -> int:
+    return max(0, min(255, value))