I'd throw the radix in on the parseInt function, just to be safe: MthFullCredit=parseInt((Prin*MonthRate)/(1-Math.pow((1+MonthRate),(-1*Nu mPayments)))*100, 10)/100; (I've had parseInt throw strange results when it assumes a different radix) sgd -- work: http://ti3.com/ non: http://thinksafely.org/