Check Brithday
<center><form><font color="#ff0000">B</font><font color="#ff3300">i</font><font color="#ff6600">r</font><font color="#ff9900">t</font><font color="#ffcc00">h</font><font color="#ffff00">d</font><font color="#ccff00">a</font><font color="#99ff00">y</font><br /><input type="text" name="month" mini:hint="phone" value="Bulan"onfocus="if(this.value="Bulan" size="5"> <input type="text" name="day" size="5" mini:hint="phone" value="Tanggal"onfocus="if(this.value="Tanggal"> <input type="text" name="year" size="5" mini:hint="phone" value="Tahun"onfocus="if(this.value="Tahun"><br><font color="#ff0000">H</font><font color="#ff3300">a</font><font color="#ff6600">s</font><font color="#ff9900">i</font><font color="#ffcc00">l</font><font color="#ffff00">n</font><font color="#ccff00">y</font><font color="#99ff00">a</font><br/><input type="text" name="birthday" size="11"><br /><input type="button" value="Check"             onclick="cala_day(this.form)"> <input type="Reset"></form>'); 

function cala_day(form) {
                var nSwitch = 0
        var nMonth = parseInt(form.month.value)
        var nDay =  parseInt(form.day.value)
        var nYear =  parseInt(form.year.value)
        
        if(!(nYear % 4) && (nMonth > 2)) {
                nSwitch = 1
        }               

        var nDayOfWeek = cala_weekday(nMonth, nDay, nYear)
        
        if(nSwitch) {
                nDayOfWeek++
                nSwitch = 0
        }
        
        day_display(form, nDayOfWeek)
}

function cala_weekday( x_nMonth, x_nDay, x_nYear) {

        if(x_nMonth >= 3){      
                x_nMonth -= 2
        }
        else {
                x_nMonth += 10
        }

        if( (x_nMonth == 11) || (x_nMonth == 12) ){
                x_nYear--
        }

        var nCentNum = parseInt(x_nYear / 100)
        var nDYearNum = x_nYear % 100
        
        var nPart1 = parseInt(2.6 * x_nMonth - .2)
        
        var nZeller = (parseInt(nPart1 + x_nDay + nDYearNum + (nDYearNum / 4) + (nCentNum / 4) - 2 * nCentNum)) % 7
        
        if(nZeller < 0){
                nZeller += 7
        }
        
        return nZeller
}

function day_display(form, x_nDayOfWeek) {

        if(x_nDayOfWeek == 0) {
                form.birthday.value = "Sabado*Sabtu" 

                return
        }
        if(x_nDayOfWeek == 1) {
                form.birthday.value = "Minggu" 


                return
        }
        if(x_nDayOfWeek == 2) {
                form.birthday.value = "Senin" 

                return
        }
        if(x_nDayOfWeek == 3) {
                form.birthday.value = "Selasa" 

                return
        }
        if(x_nDayOfWeek == 4) {
                form.birthday.value = "Rabu" 

                return
        }
        if(x_nDayOfWeek == 5) {
                form.birthday.value = "Kamis" 

                return
        }
        if(x_nDayOfWeek == 6) {
                form.birthday.value = "Jum'at" 




                return
        }

        form.birthday.value = "Salah Euy..!"
}