diff --git a/requirements.txt b/requirements.txt
old mode 100755
new mode 100644
index 48a7412..9cc6797
--- a/requirements.txt
+++ b/requirements.txt
@@ -54,7 +54,7 @@ MarkupSafe==1.0
 matplotlib==2.0.2
 mistune==0.7.4
 mock==2.0.0
-nbconvert==5.2.1
+nbconvert==6.3.0
 nbformat==4.3.0
 networkx==1.11
 nose==1.3.7