diff --git a/PeselValid.java b/PeselValid.java
new file mode 100644
index 0000000..874aa31
--- /dev/null
+++ b/PeselValid.java
@@ -0,0 +1,143 @@
+package wmiproject;
+
+public class PeselValid {
+
+	private byte PESEL[] = new byte[11];
+	private boolean valid = false;
+	 
+	public PeselValid(String PESELNumber) {
+		if (PESELNumber.length() != 11){
+			valid = false;
+		}
+		else {
+			for (int i = 0; i < 11; i++){
+			PESEL[i] = Byte.parseByte(PESELNumber.substring(i, i+1));
+			}
+			if (checkSum() && checkMonth() && checkDay()) {
+				valid = true;
+			}
+			else {
+				valid = false; 
+			}
+		}
+	}
+	 	 
+	public int getBirthYear() {
+		int year;
+		int month;
+		year = 10 * PESEL[0];
+		year += PESEL[1];
+		month = 10 * PESEL[2];
+		month += PESEL[3];
+		if (month > 80 && month < 93) {
+			year += 1800;
+		}
+		else if (month > 0 && month < 13) {
+			year += 1900;
+		}
+		else if (month > 20 && month < 33) {
+			year += 2000;
+		}
+		else if (month > 40 && month < 53) {
+			year += 2100;
+		}
+		else if (month > 60 && month < 73) {
+			year += 2200;
+		}          
+			return year;
+	}
+	 
+	public int getBirthMonth() {
+		int month;
+		month = 10 * PESEL[2];
+		month += PESEL[3];
+		if (month > 80 && month < 93) {
+			month -= 80;
+		}
+		else if (month > 20 && month < 33) {
+			month -= 20;
+		}
+		else if (month > 40 && month < 53) {
+			month -= 40;
+		}
+		else if (month > 60 && month < 73) {
+			month -= 60;
+		}          
+		return month;
+	}
+	 
+	 
+	public int getBirthDay() {
+		int day;
+		day = 10 * PESEL[4];
+		day += PESEL[5];
+		return day;
+	}
+	 	 
+	private boolean checkSum() {
+		int sum = 1 * PESEL[0] +
+		3 * PESEL[1] +
+		7 * PESEL[2] +
+		9 * PESEL[3] +
+		1 * PESEL[4] +
+		3 * PESEL[5] +
+		7 * PESEL[6] +
+		9 * PESEL[7] +
+		1 * PESEL[8] +
+		3 * PESEL[9];
+		sum %= 10;
+		sum = 10 - sum;
+		sum %= 10;
+		 
+		if (sum == PESEL[10]) {
+			return true;
+		}
+		else {
+			return false;
+		}
+	}
+	 
+	private boolean checkMonth() {
+		int month = getBirthMonth();
+		if (month > 0 && month < 13) {
+			return true;
+		}
+		else {
+			return false;
+		}
+	}
+	 
+	private boolean checkDay() {
+		int year = getBirthYear();
+		int month = getBirthMonth();
+		int day = getBirthDay();
+		if ((day >0 && day < 32) &&
+		(month == 1 || month == 3 || month == 5 ||
+		month == 7 || month == 8 || month == 10 ||
+		month == 12)) {
+			return true;
+		}
+		else if ((day >0 && day < 31) &&
+		(month == 4 || month == 6 || month == 9 ||
+		month == 11)) {
+			return true;
+		}
+		else if ((day >0 && day < 30 && leapYear(year)) ||
+		(day >0 && day < 29 && !leapYear(year))) {
+			return true;
+		}
+		else {
+			return false;
+		}      
+	}
+	 
+	private boolean leapYear(int year) {
+		if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0)
+			return true;
+		else
+			return false;
+	}
+	public boolean isValid() {
+		return valid;
+		}
+}