diff --git a/tool/helper.go b/tool/helper.go
index 2015e6a..d09ffe7 100644
--- a/tool/helper.go
+++ b/tool/helper.go
@@ -34,7 +34,7 @@ func GetOrderNumber() string {
 // ByteFmt 格式化显示文件大小
 func ByteFmt(size int64) string {
 	var unitArr = []string{"B", "KB", "MB", "GB", "TB", "EB"}
-	if size == 0 {
+	if size <= 0 {
 		return "unknown"
 	}
 	fs := float64(size)