diff --git a/demos/TTSArmLinux/src/Predictor.hpp b/demos/TTSArmLinux/src/Predictor.hpp
index 765d859be..6d4926fff 100644
--- a/demos/TTSArmLinux/src/Predictor.hpp
+++ b/demos/TTSArmLinux/src/Predictor.hpp
@@ -150,6 +150,10 @@ public:
         return wav_;
     }
 
+    int GetWavSize() {
+        return wav_.size() * sizeof(float);
+    }
+
     void ReleaseWav() {
         wav_.clear();
     }
@@ -188,7 +192,7 @@ public:
         // 写入头信息
         WavHeader header;
         header.size = sizeof(header) - 8;
-        header.data_size = wav_.size() * sizeof(float);
+        header.data_size = GetWavSize();
         header.byte_rate = header.sample_rate * header.num_channels * header.bits_per_sample / 8;
         header.block_align = header.num_channels * header.bits_per_sample / 8;
         fout.write(reinterpret_cast<const char*>(&header), sizeof(header));
diff --git a/demos/TTSArmLinux/src/main.cc b/demos/TTSArmLinux/src/main.cc
index 4068cb0b9..ceb76358f 100644
--- a/demos/TTSArmLinux/src/main.cc
+++ b/demos/TTSArmLinux/src/main.cc
@@ -60,7 +60,8 @@ int main(int argc, char *argv[]) {
         return -1;
     }
 
-    std::cout << "Inference time: " << predictor.GetInferenceTime() << "ms, WAV size: " << predictor.GetWav().size() << std::endl;
+    std::cout << "Inference time: " << predictor.GetInferenceTime() << " ms, "
+              << "WAV size (without header): " << predictor.GetWavSize() << " bytes" << std::endl;
 
     if (!predictor.WriteWavToFile(outputWavPath)) {
         std::cerr << "write wav file failed" << std::endl;