About this calculator
Extra principal payments are quietly powerful — every dollar applied early skips years of compounding interest. This calculator shows what adding a fixed amount each month, or a single annual payment, does to your loan term and lifetime interest.
What it shows you
- New payoff date with your chosen extra payment
- Total interest saved over the life of the loan
- The impact of monthly vs. annual extra payments
- Years removed from the original term
- A comparison across several extra-payment amounts
What you'll enter
- Loan amount, interest rate, and remaining term
- Extra monthly, quarterly, or yearly principal payments
- One-time lump sums, with the month and year to apply each
When to use it
- Planning a regular extra principal payment
- Deciding where a bonus or windfall goes
- Seeing how much sooner the loan could be paid off
Why it matters
Borrowers underestimate how much early principal matters. Seeing that "$150 a month saves $60,000 and five years" reframes a small habit as a major wealth decision — and a memorable advisor moment.
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