diff --git a/docs/changelog.rst b/docs/changelog.rst
index 30de31d..cfcc31c 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -1,6 +1,10 @@
 Changelog
 =========
 
+1.9.1
+-----
+* Fix unreferenced piece size error in CLI
+
 1.9.0
 -----
 * Increase MAX_PIECE_SIZE to 64 MiB
diff --git a/dottorrent/cli.py b/dottorrent/cli.py
index 03e0fd4..9762956 100755
--- a/dottorrent/cli.py
+++ b/dottorrent/cli.py
@@ -76,6 +76,8 @@ def main():
             piece_size = int(args.piece_size)
         else:
             piece_size = parse_size(args.piece_size, binary=True)
+    else:
+        piece_size = None
 
     if args.date:
         if args.date.isdigit():
diff --git a/dottorrent/version.py b/dottorrent/version.py
index e5102d3..35424e8 100644
--- a/dottorrent/version.py
+++ b/dottorrent/version.py
@@ -1 +1 @@
-__version__ = '1.9.0'
+__version__ = '1.9.1'