diff --git a/programs/fileio.c b/programs/fileio.c
index 1f1cbb9e..fd2a0bda 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -1509,7 +1509,7 @@ FIO_compressFilename_internal(FIO_ctx_t* const fCtx,
     U64 readsize = 0;
     U64 compressedfilesize = 0;
     U64 const fileSize = UTIL_getFileSize(srcFileName);
-    DISPLAYLEVEL(5, "%s: %u bytes \n", srcFileName, (unsigned)fileSize);
+    DISPLAYLEVEL(5, "%s: %llu bytes \n", srcFileName, (unsigned long long)fileSize);
 
     /* compression format selection */
     switch (prefs->compressionType) {