diff --git a/src/main/java/src/TasksFrame.java b/src/main/java/src/TasksFrame.java
index 615f647..26ca4a0 100644
--- a/src/main/java/src/TasksFrame.java
+++ b/src/main/java/src/TasksFrame.java
@@ -6,6 +6,7 @@ import java.awt.*;
 import java.awt.event.ActionEvent;
 import java.awt.event.ActionListener;
 import java.util.ArrayList;
+import java.util.LinkedList;
 
 public class TasksFrame extends JFrame {
 
@@ -74,6 +75,68 @@ public class TasksFrame extends JFrame {
 
         setupLeibnizR(1000);
 
+        setupEulerschePhiFunk();
+
+    }
+
+    private void setupEulerschePhiFunk() {
+
+        JPanel jPanel = setupPanel("Eulersche Phi Funktion");
+
+        Button button = new Button("Calc Phi");
+        button.setVisible(true);
+        button.setBounds(120, 50, 100,  30);
+
+        JTextField jTextField = new JTextField();
+        jTextField.setVisible(true);
+        jTextField.setBounds( 10, 40,  60, 20);
+
+        JLabel jLabel = new JLabel();
+        jLabel.setVisible(true);
+        jLabel.setBounds(10, 90, 60, 30);
+
+
+        jPanel.add(button);
+        jPanel.add(jTextField);
+        jPanel.add(jLabel);
+
+        button.addActionListener(new ActionListener() {
+            @Override
+            public void actionPerformed(ActionEvent e) {
+                int r = ePhi(Integer.valueOf(jTextField.getText()));
+                jLabel.setText(String.valueOf(r));
+            }
+        });
+
+
+    }
+
+    public int ePhi(Integer n) {
+
+        LinkedList<Object> menge = new LinkedList<>();
+
+        for(int k =1; k<=n; k++){
+            if(ggt(k, n)== 1){
+                menge.add(k);
+            }
+        }
+        return menge.size();
+    }
+
+   public int ggt(int a, int b) {
+
+        int h;
+        if (a == 0) return 0;
+        if (b == 0) return 0;
+
+        do {
+            h = a % b;
+            a = b;
+            b = h;
+        } while (b != 0);
+
+        return a;
+
     }
 
     private void setupHelloWorld() {
diff --git a/src/test/java/src/TasksFrameTest.java b/src/test/java/src/TasksFrameTest.java
index 953a426..c7de36d 100644
--- a/src/test/java/src/TasksFrameTest.java
+++ b/src/test/java/src/TasksFrameTest.java
@@ -7,16 +7,14 @@ import static org.junit.jupiter.api.Assertions.*;
 class TasksFrameTest {
 
     @Test
-    void setupLeibnizR()
-    {
+    void setupLeibnizR() {
         TasksFrame tasksFrame = new TasksFrame();
         double x = tasksFrame.setupLeibnizR(100000);
         assertEquals(Math.PI/4, x, 0.00001, "Die Werte sind unterschiedlich. Soll: 0.785 Ist:" +x);
     }
 
     @Test
-    void setupDiff()
-    {
+    void setupDiff(){
         TasksFrame frame = new TasksFrame();
         int diff = frame.calcDiff(6, 7);
         assertEquals(-1, diff);
@@ -27,8 +25,7 @@ class TasksFrameTest {
     }
 
     @Test
-    void setupSumm()
-    {
+    void setupSumm(){
         TasksFrame frame = new TasksFrame();
         int sum1 = frame.calcSumm(23, 11);
         assertEquals(34, sum1);
@@ -39,8 +36,7 @@ class TasksFrameTest {
     }
 
     @Test
-    void setupSumFromTo()
-    {
+    void setupSumFromTo(){
         TasksFrame frame = new TasksFrame();
         int p1= frame.sumCalc(1,5);
         assertEquals(15,p1);
@@ -50,6 +46,29 @@ class TasksFrameTest {
         assertEquals(3,p3);
     }
 
+    @Test
+    void test_ePhi(){
+        TasksFrame tasksFrame = new TasksFrame();
+        int i = tasksFrame.ePhi( 10);
+        assertEquals(4, i);
+        int a = tasksFrame.ePhi(25);
+        assertEquals(20, a);
+        int b = tasksFrame.ePhi(15);
+        assertEquals(8, b);
+        int c = tasksFrame.ePhi(35);
+        assertEquals(24, c);
+    }
+
+    @Test
+    void test_ggt(){
+        TasksFrame tasksFrame = new TasksFrame();
+        int ggt1 = tasksFrame.ggt(4, 20);
+        assertEquals(4, ggt1);
+        int ggt2 = tasksFrame.ggt(205, 120);
+        assertEquals(5, ggt2);
+        int ggt3 = tasksFrame.ggt(262, 599);
+        assertEquals(1, ggt3);
+    }
     @Test
     void setupArea()
     {