diff --git a/pywal/colors.py b/pywal/colors.py
index e4fae46..ddf1899 100644
--- a/pywal/colors.py
+++ b/pywal/colors.py
@@ -75,7 +75,7 @@ def generic_adjust(colors, light):
 
 def saturate_colors(colors, amount):
     """Saturate all colors."""
-    if float(amount) <= 1.0:
+    if amount and float(amount) <= 1.0:
         for i, _ in enumerate(colors):
             if i not in [0, 7, 8, 15]:
                 colors[i] = util.saturate_color(colors[i], float(amount))