diff --git a/src/main/java/de/neemann/digital/core/element/Keys.java b/src/main/java/de/neemann/digital/core/element/Keys.java
index 80f736f35..eccbb9362 100644
--- a/src/main/java/de/neemann/digital/core/element/Keys.java
+++ b/src/main/java/de/neemann/digital/core/element/Keys.java
@@ -105,6 +105,15 @@ public final class Keys {
             .setComboBoxValues(2, 3, 4, 5)
             .setMin(2);
 
+    /**
+     * number of inputs in the LUT
+     */
+    public static final Key.KeyInteger LUT_INPUT_COUNT
+            = new Key.KeyInteger("Inputs", 6)
+            .setComboBoxValues(2, 3, 4, 5, 6)
+            .setMax(20)
+            .setMin(2);
+
 
     /**
      * The counter max value
diff --git a/src/main/java/de/neemann/digital/core/memory/LookUpTable.java b/src/main/java/de/neemann/digital/core/memory/LookUpTable.java
index 16a9471bc..774fc120b 100644
--- a/src/main/java/de/neemann/digital/core/memory/LookUpTable.java
+++ b/src/main/java/de/neemann/digital/core/memory/LookUpTable.java
@@ -34,7 +34,7 @@ public class LookUpTable extends Node implements Element {
     }
             .addAttribute(Keys.ROTATE)
             .addAttribute(Keys.BITS)
-            .addAttribute(Keys.INPUT_COUNT)
+            .addAttribute(Keys.LUT_INPUT_COUNT)
             .addAttribute(Keys.LABEL)
             .addAttribute(Keys.DATA)
             .supportsHDL();