🏠 Loan Amortization Calculator
Estimate payment, payoff time, total interest, and savings from additional monthly payments.
Try the calculator
The values below are a working example. Change any field to recalculate instantly in your browser.
Estimate excludes lender fees, taxes, and insurance.
Formula & Mathematical Logic
Payment = P × r(1+r)ⁿ / ((1+r)ⁿ − 1)The standard amortization formula uses principal P, monthly interest rate r, and number of monthly payments n. Extra payments reduce principal sooner. Calculations run locally in your browser.
Worked Example
A $250,000 loan at 6.5% for 20 years has a scheduled payment of about $1,863.93 per month before fees.
Frequently Asked Questions
How is this result calculated?
The calculator simulates the remaining balance month by month and applies any extra payment directly to principal.
Does Calcixa upload my inputs?
No. Inputs and results remain in your browser and are not sent to a Calcixa server.
CALCIXA PRACTICAL GUIDE
How to use the Loan Amortization Calculator
An amortization model follows a reducing loan balance month by month. Each scheduled payment first covers that period’s interest and then reduces principal; optional extra payments accelerate principal reduction and can shorten the payoff period.
This tool is suited to fixed-rate planning. It excludes lender fees, escrow, insurance, taxes, prepayment restrictions, rate changes, and payment-date conventions unless explicitly shown.
Step-by-step
- Enter principal, annual rate, and original term.
- Add only an extra monthly amount you can sustain.
- Calculate the scheduled payment, projected payoff time, and interest.
- Compare the base and extra-payment scenarios, then verify that the lender applies prepayments to principal without penalty.
How to read the result
- Scheduled payment is the fixed principal-and-interest amount before extras.
- Payoff time falls when extra amounts reduce principal early.
- Interest saved is modelled by comparing the base schedule with the extra-payment schedule.
Common mistakes to avoid
- Assuming every lender handles extra payments identically.
- Including tax or insurance inside a principal-and-interest payment field.
- Ignoring floating rates and prepayment charges.
Important: This educational estimate is not financial, investment, tax, or lending advice.
More questions about Loan Amortization Calculator
Why do early payments contain more interest?
Interest is calculated on the outstanding balance, which is largest near the start of the schedule.
Does one extra payment have the same effect as monthly extras?
Timing matters: reducing principal earlier generally avoids more future interest.
Can the tool replace a lender payoff statement?
No. A payoff statement includes exact dates, accrued interest, fees, and account-specific adjustments.
Sources and methodology
Calcixa explains the model, assumptions, and limitations so you can verify the result. See our calculation and tool methodology for rounding, privacy, testing, and correction practices.
Maintained by the Calcixa product team. This page was last updated on 7 September 2026.