diff --git a/src/llama-vocab.cpp b/src/llama-vocab.cpp
index 735c5d547f9e4..97f374eac9570 100644
--- a/src/llama-vocab.cpp
+++ b/src/llama-vocab.cpp
@@ -1013,7 +1013,7 @@ struct llm_tokenizer_ugm_session {
         }
     private:
         uint32_t get_node(size_t index) {
-            if (index > xcda_array_size) {
+            if (index >= xcda_array_size) {
                 throw std::runtime_error("Index out of array bounds in XCDA array!");
             }
             return xcda_array[index];