diff --git a/programs/fileio.c b/programs/fileio.c
index 2e8e4a6f6..d5da78479 100644
--- a/programs/fileio.c
+++ b/programs/fileio.c
@@ -918,7 +918,7 @@ int getFileInfo(fileInfo_t* info, const char* inFileName){
             fread(frameHeader, totalFrameHeaderBytes, 1, srcFile);
 
             /* get decompressed file size */
-            info->decompressedSize = ZSTD_getFrameContentSize(frameHeader, totalFrameHeaderBytes);
+            info->decompressedSize += ZSTD_getFrameContentSize(frameHeader, totalFrameHeaderBytes);
 
             /* check if checksum is used */
             if(contentChecksumFlag){