diff --git a/projjpn/src/main/java/de/hs_fulda/ciip/projjpn/Birthdate.java b/projjpn/src/main/java/de/hs_fulda/ciip/projjpn/Birthdate.java
index ab9af4c..32ed901 100644
--- a/projjpn/src/main/java/de/hs_fulda/ciip/projjpn/Birthdate.java
+++ b/projjpn/src/main/java/de/hs_fulda/ciip/projjpn/Birthdate.java
@@ -43,13 +43,13 @@ public class Birthdate {
 	}
 	
 	public boolean isValid(int DD, int MM, int YYYY) {
-		if (DD < 1) {
+		if (DD < 1 || DD > 31) {
 			return false;
 		}
-		if (MM < 1) {
+		if (MM < 1 || MM > 12) {
 			return false;
 		}
-		if (YYYY < 1) {
+		if (YYYY < 1990 || YYYY > 2022) {
 			return false;
 		}
 		
diff --git a/projjpn/src/test/java/de/hs_fulda/ciip/projjpn/BirthdateTest.java b/projjpn/src/test/java/de/hs_fulda/ciip/projjpn/BirthdateTest.java
index 8b3ea01..b584b58 100644
--- a/projjpn/src/test/java/de/hs_fulda/ciip/projjpn/BirthdateTest.java
+++ b/projjpn/src/test/java/de/hs_fulda/ciip/projjpn/BirthdateTest.java
@@ -39,6 +39,25 @@ public class BirthdateTest extends TestCase {
 		boolean expectedResult = false;
 		boolean gotResult = birthdate.isValid(0, 0, 0);
 		assertEquals(expectedResult, gotResult);
+		
+		gotResult = birthdate.isValid(32, 13, 1990);
+		assertEquals(expectedResult, gotResult);
+		
+		gotResult = birthdate.isValid(31, 0, 1980);
+		assertEquals(expectedResult, gotResult);
+		
+		gotResult = birthdate.isValid(31, 13, 1980);
+		assertEquals(expectedResult, gotResult);
+		
+		gotResult = birthdate.isValid(1, 1, 3000);
+		assertEquals(expectedResult, gotResult);
+		
+		gotResult = birthdate.isValid(1, 1, 1900);
+		assertEquals(expectedResult, gotResult);
+		
+		expectedResult = true;
+		gotResult = birthdate.isValid(1, 5, 2020);
+		assertEquals(expectedResult, gotResult);
 	}
 	
 }