2 free ways to Pay Off Your Mortgage Early

Pay half of your regular monthly payment every two weeks. (aka) biweekly mortgage payment ( Do not pay a fee to initiate a biweekly mortgage plan, DIY.  Instead of making a single monthly mortgage payment each month, pay 1/2 of the monthly payment on the 1st of the month, and the other half on the 15th). 
Biweekly vs Monthly payment saving calculator
http://www.mtgprofessor.com/Calculators/Calculator2bi.html


Make one extra payment a year. pay one extra month's mortgage payment in one payment. (Extra payments cut mortgage by 12 years !)
calculator for extra payment and payoff year
http://www.interest.com/mortgage/calculators/mortgage-calculator/