diff --git a/requirements.txt b/requirements.txt
index 4b8d92d..5fc46aa 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,7 +6,7 @@
 #
 commandlines==0.4.1
     # via font-line (setup.py)
-fonttools==4.38.0
+fonttools==4.39.3
     # via font-line (setup.py)
 standardstreams==0.2.0
     # via font-line (setup.py)