Quick start
- Open the Amortization Calculator.
- Enter loan amount, annual rate, and term.
- Use the first example, "Extra payment: $200,000 at 6%, 30 years, +$100/month", if you want to see a filled-out estimate before entering your own values.
- Calculate, read the formula line, then copy the result only after the amounts, rates, and term look right.
Best uses
Use this guide when one of these tasks matches what you are trying to do.
- Estimate how a loan balance pays down over time.
- Compare scheduled payoff with extra monthly payments.
- Estimate interest saved by paying more than the required amount.
- Understand how monthly interest affects principal reduction.
What this calculator is for
The Amortization Calculator shows how a fixed loan pays down over time. It also estimates the payoff time and interest saved when you add extra monthly payments.
Use it when you want to: Estimate how a loan balance pays down over time. Compare scheduled payoff with extra monthly payments.
What to enter
Finance estimates are sensitive to small input changes. Check whether a field expects a monthly amount, annual amount, dollar value, or percent before calculating.
- Enter loan amount, annual rate, and term.
- Enter extra monthly payment only if you plan to pay above the scheduled payment.
- Keep the extra amount realistic so the comparison is useful.
Example walkthrough
Try the calculator example: Extra payment: $200,000 at 6%, 30 years, +$100/month. The example result is Payoff time and interest saved.
- For $200,000 at 6% for 30 years, the scheduled payment is calculated first.
- Adding $100/month reduces the balance faster, which lowers future interest.
Formula and steps
The calculator starts with the scheduled amortized payment, then simulates monthly interest and principal reduction with any extra payment you enter.
The formula line on the calculator page is there so the number is not a black box. Read it before using the answer in a budget, comparison, or planning note.
How to read the answer
Start with the headline result, then use the supporting metrics to understand what made the result larger or smaller.
- Scheduled payment is the normal fixed payment before extra money.
- Months saved compares the original term with the extra-payment payoff.
- Interest saved is an estimate before fees, penalties, or servicer rules.
Common mistakes to avoid
Most bad finance estimates come from mixing rates, terms, monthly amounts, and annual amounts. The other common mistake is using a planning estimate as if it were a final quote.
- Do not assume extra payments are always applied to principal without checking the lender.
- Do not ignore prepayment penalties.
- Do not use this for variable-rate or interest-only loans.
What to try next
A related calculator can help check the same money question from another angle before you rely on one result.
- Use Mortgage Calculator for housing costs beyond principal and interest.
- Use Loan Calculator for a plain payment estimate.
Sources and estimate notes
This guide links to public financial, consumer, statistical, or tax references where they are useful for understanding the calculator context.
Source links improve transparency, but they do not turn a quick calculator into professional advice or a final loan, tax, payroll, or investment answer.
Examples from the calculator
Payoff time and interest saved
Scheduled payoff estimate
Faster payoff, lower interest
Common questions
What can I use the Amortization Calculator for?
Use it for quick planning, comparison, and what-if estimates before you check exact numbers with a lender, tax professional, payroll provider, or financial adviser.
How does the Amortization Calculator calculate the result?
The calculator starts with the scheduled amortized payment, then simulates monthly interest and principal reduction with any extra payment you enter.
Is this financial, tax, or legal advice?
This calculator gives an educational estimate only. It does not include every fee, lender rule, tax rule, local rate, credit, penalty, or personal financial detail.
Related tools
- Mortgage Calculator Estimate monthly principal, interest, taxes, insurance, PMI, and HOA costs.
- Loan Calculator Estimate a fixed monthly loan payment and total interest.
- Payment Calculator Find a fixed monthly payment from amount, rate, and term.
History, privacy, and copying
Recent answers stay visible in the page while you work. The history is kept only in the current browser tab and is not sent to a server.
Copy answer copies the expression and result so you can paste it into notes, homework, a message, or another document.