diff --git a/gui/qt/paytoedit.py b/gui/qt/paytoedit.py
index 0151e0f3..83881e79 100644
--- a/gui/qt/paytoedit.py
+++ b/gui/qt/paytoedit.py
@@ -186,8 +186,9 @@ class PayToEdit(ScanQRTextEdit):
         self.update_size()
 
     def update_size(self):
+        lineHeight = QFontMetrics(self.document().defaultFont()).height()
         docHeight = self.document().size().height()
-        h = docHeight*17 + 11
+        h = docHeight * lineHeight + 11
         if self.heightMin <= h <= self.heightMax:
             self.setMinimumHeight(h)
             self.setMaximumHeight(h)