diff --git a/compression/JFJochCompressor.h b/compression/JFJochCompressor.h
index c6ce2ab1..826b804b 100644
--- a/compression/JFJochCompressor.h
+++ b/compression/JFJochCompressor.h
@@ -41,7 +41,7 @@ private:
 };
 
 template <class T> std::vector<T> bitshuffle(const std::vector<T> &input, size_t block_size) {
-    std::vector<T> ret(input.size() * sizeof(T));
+    std::vector<T> ret(input.size());
     bshuf_bitshuffle(input.data(), ret.data(), input.size(), sizeof(T), block_size);
     return ret;
 }