Extra Payment Calculator

Even small extra payments have a dramatic effect. An extra $200/month on a $300,000 30-year mortgage at 6.5% saves over $80,000 in interest and pays off the loan about 8 years early. The effect is largest in the early years when the balance is highest.

If your loan rate is 6.5% and you expect 7–10% from investments, investing may return more mathematically. But paying down debt is a guaranteed, risk-free return equal to your interest rate. Both are good choices — consider your risk tolerance, tax situation, and peace of mind.

A lump sum payment is a one-time extra amount applied directly to your principal. It immediately reduces the balance on which interest is calculated. Common sources are tax refunds, bonuses, or a windfall. This calculator shows the impact of a lump sum alongside your regular extra payments.