diff --git a/benchmarks/benchmark_dataset.py b/benchmarks/benchmark_dataset.py
index 5d2a26cd443c..8671719bce72 100644
--- a/benchmarks/benchmark_dataset.py
+++ b/benchmarks/benchmark_dataset.py
@@ -353,7 +353,7 @@ def sample(
                 : input_lens[i]
             ]
             prompt = tokenizer.decode(re_encoded_sequence)
-            total_input_len = prefix_len + int(input_lens[i])
+            total_input_len = len(re_encoded_sequence)
             requests.append(
                 SampleRequest(
                     prompt=prompt,