diff --git a/Project_Model/Tests/spanned_masker_test.py b/Project_Model/Tests/spanned_masker_test.py
index e78d04e..3b70491 100644
--- a/Project_Model/Tests/spanned_masker_test.py
+++ b/Project_Model/Tests/spanned_masker_test.py
@@ -8,30 +8,26 @@ VOCABULARY_PATH = Path("Assets/Model/toy_10/toy_dictionary.json")
 VOCABULARY = BPE.load_nanos_vocabulary(VOCABULARY_PATH)
 SPECIAL_LIST = BPE.default_special_tokens()
 
+
 class TestSpannedMasker:
 
     def test_spanned_masking(self):
 
         CORPUS_PATH = Path("Project_Model/Tests/spanner_file/mask.txt")
         TEXT = CORPUS_PATH.read_text("utf-8")
+        CORRUPTION_PERCENTAGE = 0.15
+        TOLERANCE = 0.05
 
-        TOKENIZER = BPE.TokeNanoCore(
-            VOCABULARY,
-            SPECIAL_LIST
-        )
+        TOKENIZER = BPE.TokeNanoCore(VOCABULARY, SPECIAL_LIST)
         VOCABULARY_SIZE = TOKENIZER.vocabulary_size
 
-        MASKER = Transformer.SpannedMasker(0.4,average_span=3)
+        MASKER = Transformer.SpannedMasker(CORRUPTION_PERCENTAGE, 3)
 
         TOKENS = TOKENIZER.encode(TEXT)
 
-        LEGAL_TOKENS: set[int] = set(TOKENIZER.encode(
-            "<SUBJ><OBJ><PRED>"
-        ))
+        LEGAL_TOKENS: set[int] = set(TOKENIZER.encode("<SUBJ><OBJ><PRED>"))
 
-        SPECIAL_TOKENS: set[int] = set(TOKENIZER.encode(
-            "".join(SPECIAL_LIST)
-        ))
+        SPECIAL_TOKENS: set[int] = set(TOKENIZER.encode("".join(SPECIAL_LIST)))
 
         ILLEGAL_TOKENS: set[int] = SPECIAL_TOKENS.difference(LEGAL_TOKENS)
 
@@ -40,34 +36,52 @@ class TestSpannedMasker:
 
         OUTPUT, TARGET = MASKER.mask_sequence(TOKENS, VOCABULARY_SIZE, ILLEGAL_TOKENS)
 
-        UNCORRUPTED_TOKENS = list(filter(lambda token: token <= VOCABULARY_SIZE, OUTPUT))
+        UNCORRUPTED_TOKENS = list(
+            filter(lambda token: token <= VOCABULARY_SIZE, OUTPUT)
+        )
         CORRUPTED_TOKENS = list(filter(lambda token: token <= VOCABULARY_SIZE, TARGET))
 
         TARGET.append(END_FORMATTER)
 
-        OUTPUT = list(map(lambda token: SPECIAL_FORMATTER if token > VOCABULARY_SIZE else token, OUTPUT))
-        TARGET = list(map(lambda token: SPECIAL_FORMATTER if token > VOCABULARY_SIZE else token, TARGET))
+        OUTPUT = list(
+            map(
+                lambda token: SPECIAL_FORMATTER if token > VOCABULARY_SIZE else token,
+                OUTPUT,
+            )
+        )
+        TARGET = list(
+            map(
+                lambda token: SPECIAL_FORMATTER if token > VOCABULARY_SIZE else token,
+                TARGET,
+            )
+        )
 
         OUT_TEXT = TOKENIZER.decode(OUTPUT)
         TAR_TEXT = TOKENIZER.decode(TARGET)
 
+        ACTUAL_CORRUPTION_PERCENTAGE = len(CORRUPTED_TOKENS) / len(TOKENS)
+
         print(f"Original text:\n\n{TEXT}")
         print(f"Inputs:\n\n{OUT_TEXT}")
         print(f"Targets:\n\n{TAR_TEXT}")
+        print(f"Target Tokens:\n\n{OUTPUT}")
 
-        print("\n".join([
-            f"======================",
-            f"Original length: {len(TOKENS)}",
-            f"Uncorrupted Chars: {len(UNCORRUPTED_TOKENS)}",
-            f"Corrupted Chars: {len(CORRUPTED_TOKENS)}",
-            f"Percentage_corruption: {(len(CORRUPTED_TOKENS)/len(TOKENS))*100}%",
-            f"======================"
-        ]))
+        print(
+            "\n".join(
+                [
+                    f"======================",
+                    f"Original length: {len(TOKENS)}",
+                    f"Uncorrupted Chars: {len(UNCORRUPTED_TOKENS)}",
+                    f"Corrupted Chars: {len(CORRUPTED_TOKENS)}",
+                    f"Percentage_corruption: {(len(CORRUPTED_TOKENS)/len(TOKENS))*100}%",
+                    f"======================",
+                ]
+            )
+        )
 
+        assert ACTUAL_CORRUPTION_PERCENTAGE > CORRUPTION_PERCENTAGE - TOLERANCE
+        assert ACTUAL_CORRUPTION_PERCENTAGE < CORRUPTION_PERCENTAGE + TOLERANCE
 
 
 if __name__ == "__main__":
     TestSpannedMasker().test_spanned_masking()
-
-
-