diff --git a/core-java-modules/core-java-numbers-3/src/test/java/com/baeldung/integerToBinary/IntegerToBinaryUnitTest.java b/core-java-modules/core-java-numbers-3/src/test/java/com/baeldung/integerToBinary/IntegerToBinaryUnitTest.java
index 38ae79f2f5..9439f012e3 100644
--- a/core-java-modules/core-java-numbers-3/src/test/java/com/baeldung/integerToBinary/IntegerToBinaryUnitTest.java
+++ b/core-java-modules/core-java-numbers-3/src/test/java/com/baeldung/integerToBinary/IntegerToBinaryUnitTest.java
@@ -1,6 +1,8 @@
 package com.baeldung.integerToBinary;
 
+import org.apache.commons.lang3.StringUtils;
 import org.junit.Test;
+
 import static org.junit.Assert.assertEquals;
 
 public class IntegerToBinaryUnitTest {
@@ -24,4 +26,18 @@ public class IntegerToBinaryUnitTest {
         String binaryString = Integer.toString(n, 2);
         assertEquals("111", binaryString);
     }
-}
+
+    @Test
+    public void givenAnInteger_whenFormatAndReplaceCalled_thenZeroPaddedBinaryString() {
+        int n = 7;
+        String binaryString = String.format("%8s", Integer.toBinaryString(n)).replace(" ", "0");
+        assertEquals("00000111", binaryString);
+    }
+
+    @Test
+    public void givenAnInteger_whenUsingApacheStringUtils_thenZeroPaddedBinaryString() {
+        int n = 7;
+        String binaryString = StringUtils.leftPad(Integer.toBinaryString(n), 8, "0");
+        assertEquals("00000111", binaryString);
+    }
+}
\ No newline at end of file