See your payoff date and total interest, then use extra or biweekly payments to bring the date forward. The balance chart shows exactly when you cross the finish line.
Add extra principal each month, switch to biweekly payments, or make lump-sum payments. Each reduces the balance interest is charged on, compounding your savings.
Most modern U.S. mortgages have no prepayment penalty, but check your loan documents to be sure before making large extra payments.