diff --git a/src/binwalk/modules/heuristics.py b/src/binwalk/modules/heuristics.py
index eb7a6c9..23bfdaf 100644
--- a/src/binwalk/modules/heuristics.py
+++ b/src/binwalk/modules/heuristics.py
@@ -101,7 +101,7 @@ class HeuristicCompressionAnalyzer(Module):
                    long='trigger',
                    kwargs={'trigger_level' : 0},
                    type=float,
-                   description='Set the entropy trigger level (0.0 - 1.0)'),
+                   description='Set the entropy trigger level (0.0 - 1.0, default: %.2f)' % ENTROPY_TRIGGER),
     ]
 
     KWARGS = [
@@ -114,6 +114,12 @@ class HeuristicCompressionAnalyzer(Module):
 
         self.HEADER[-1] = "HEURISTIC ENTROPY ANALYSIS"
 
+        # Trigger level sanity check
+        if self.trigger_level > 1.0:
+            self.trigger_level = 1.0
+        elif self.trigger_level < 0.0:
+            self.trigger_level = 0.0
+
         if self.config.block:
             self.block_size = self.config.block
         else: