diff --git a/html/fcl/tipper.js b/html/fcl/tipper.js
index 4688cef..dd0d45a 100644
--- a/html/fcl/tipper.js
+++ b/html/fcl/tipper.js
@@ -100,6 +100,9 @@ class FunctionBlock_tipper {
 			sum_tip += this.defuzzify_tip[i];
 			wsum_tip += x * this.defuzzify_tip[i];
 		}
+		if (sum_tip == 0) {
+			sum_tip = 1.0;
+		}
 		this.tip = wsum_tip / sum_tip;
 	}
 
diff --git a/out/artifacts/jFuzzyLogic_jar/jFuzzyLogic.jar b/out/artifacts/jFuzzyLogic_jar/jFuzzyLogic.jar
index 5c7a3aa..c071a2d 100644
Binary files a/out/artifacts/jFuzzyLogic_jar/jFuzzyLogic.jar and b/out/artifacts/jFuzzyLogic_jar/jFuzzyLogic.jar differ
diff --git a/src/main/java/net/sourceforge/jFuzzyLogic/defuzzifier/DefuzzifierCenterOfGravity.java b/src/main/java/net/sourceforge/jFuzzyLogic/defuzzifier/DefuzzifierCenterOfGravity.java
index bb98cd5..5323ec8 100644
--- a/src/main/java/net/sourceforge/jFuzzyLogic/defuzzifier/DefuzzifierCenterOfGravity.java
+++ b/src/main/java/net/sourceforge/jFuzzyLogic/defuzzifier/DefuzzifierCenterOfGravity.java
@@ -68,6 +68,9 @@ public class DefuzzifierCenterOfGravity extends DefuzzifierContinuous {
 		out.append("\t\t\t" + sumName + " += this." + defuzzName + "[i];\n");
 		out.append("\t\t\t" + wsumName + " += x * this." + defuzzName + "[i];\n");
 		out.append("\t\t}\n");
+		out.append("\t\tif (" + sumName + " == 0) {\n");
+		out.append("\t\t\t" + sumName + " = 1.0;\n");
+		out.append("\t\t}\n");
 		out.append("\t\tthis." + variable.getName() + " = " + wsumName + " / " + sumName + ";\n");
 		return out.toString();
 	}