diff --git a/core/src/processing/data/DoubleList.java b/core/src/processing/data/DoubleList.java
index f33f024cc..e9919b3e1 100644
--- a/core/src/processing/data/DoubleList.java
+++ b/core/src/processing/data/DoubleList.java
@@ -681,6 +681,9 @@ public class DoubleList implements Iterable<Double> {
    * Return a random value from the list.
    */
   public double random() {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this DoubleList");
+    }
     return data[(int) (Math.random() * count)];
   }
 
@@ -690,6 +693,9 @@ public class DoubleList implements Iterable<Double> {
    * randomSeed() from the specified sketch object.
    */
   public double random(PApplet sketch) {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this DoubleList");
+    }
     return data[(int) sketch.random(count)];
   }
 
diff --git a/core/src/processing/data/FloatList.java b/core/src/processing/data/FloatList.java
index 670b52a16..68a4703fd 100644
--- a/core/src/processing/data/FloatList.java
+++ b/core/src/processing/data/FloatList.java
@@ -703,6 +703,9 @@ public class FloatList implements Iterable<Float> {
    * Return a random value from the list.
    */
   public float random() {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this FloatList");
+    }
     return data[(int) (Math.random() * count)];
   }
 
@@ -712,6 +715,9 @@ public class FloatList implements Iterable<Float> {
    * randomSeed() from the specified sketch object.
    */
   public float random(PApplet sketch) {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this FloatList");
+    }
     return data[(int) sketch.random(count)];
   }
 
diff --git a/core/src/processing/data/IntList.java b/core/src/processing/data/IntList.java
index 6ef0b3f8b..d656a9419 100644
--- a/core/src/processing/data/IntList.java
+++ b/core/src/processing/data/IntList.java
@@ -678,6 +678,9 @@ public class IntList implements Iterable<Integer> {
    * Return a random value from the list.
    */
   public int random() {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this IntList");
+    }
     return data[(int) (Math.random() * count)];
   }
 
@@ -687,6 +690,9 @@ public class IntList implements Iterable<Integer> {
    * randomSeed() from the specified sketch object.
    */
   public int random(PApplet sketch) {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this IntList");
+    }
     return data[(int) sketch.random(count)];
   }
 
diff --git a/core/src/processing/data/StringList.java b/core/src/processing/data/StringList.java
index f7b6e6b4d..bedbf723f 100644
--- a/core/src/processing/data/StringList.java
+++ b/core/src/processing/data/StringList.java
@@ -581,6 +581,9 @@ public class StringList implements Iterable<String> {
    * Return a random value from the list.
    */
   public String random() {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this StringList");
+    }
     return data[(int) (Math.random() * count)];
   }
 
@@ -590,6 +593,9 @@ public class StringList implements Iterable<String> {
    * randomSeed() from the specified sketch object.
    */
   public String random(PApplet sketch) {
+    if (count == 0) {
+      throw new ArrayIndexOutOfBoundsException("No entries in this StringList");
+    }
     return data[(int) sketch.random(count)];
   }
 
diff --git a/core/todo.txt b/core/todo.txt
index 37cc53755..fa0605fde 100644
--- a/core/todo.txt
+++ b/core/todo.txt
@@ -1,5 +1,8 @@
 1287 (4.0.2)
 X Updating PApplet to use Java 17 (switch statements, etc)
+X XxxList bug with random() if there are zero elements in the array
+X   now throws ArrayIndexOutOfBoundsException
+X   kinda want to return null, but later getting an NPE is more confusing
 
 
 _ concurrent StringDict et al