See how extra payments and a one-time lump sum change your payoff date, total interest, and remaining balance — with live charts tuned for clarity.
Enter your loan amount, APR, and term. The calculator always compares the standard amortizing payment for that loan to a plan where you can add a higher recurring payment, an extra amount each period, and/or a lump sum on the first period.
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Keep going
Each calculator works standalone, but they pair beautifully with the others in the toolkit.
Generate a full amortization schedule with expandable yearly rows.
Compare renting and buying with simple cash-flow style totals.
Compare two loans with different rates, terms, and closing costs.
Frequently asked
The math is straightforward, but a few details trip people up. Here are the questions we answer most often.