What is an amortized loan?

An amortized loan is repaid in fixed periodic payments that cover both interest and principal. Early payments are interest-heavy, shifting toward principal over time.

What’s the difference between monthly and quarterly payments?

Monthly payments mean 12 payments per year; quarterly means 4. Fewer payments per year typically result in higher interest accrued between payments.

APR vs APY (compounding) — which should I choose?

APR is a nominal annual rate (often paired with monthly compounding for loans). APY reflects the effect of compounding over a year. This tool lets you choose monthly or annual compounding to match your loan terms.

Can I calculate with a 0% interest rate?

Yes. The calculator handles a zero rate by dividing the principal evenly across the total number of payments.

Are my inputs private?

Yes. All calculations happen locally in your browser; nothing is uploaded or stored.

Amortized Loan Calculator — Monthly or Quarterly Payments

Private by design — everything runs locally in your browser.

Inputs

Results

Summary

Payment Every Month $0.00

Total of 0 Payments $0.00

Total Interest $0.00

Understanding Amortized Loans

An amortized loan is a type of loan with scheduled, periodic payments that are applied to both the loan's principal amount and the interest accrued.

Key Components

Principal: The original amount borrowed.
Interest: The cost of borrowing the principal.
Loan Term: How long you repay the loan.
Payment: Fixed amount each period covering principal and interest.

How it Amortizes

Early payments are interest-heavy; later ones go increasingly to principal, which the amortization table makes clear.

Loan Calculator FAQ

How accurate is it?

It uses the standard fixed-rate amortization formula. Minor differences can occur if a lender uses slightly different conventions.

Does it work for any loan?

Yes—mortgages, auto, and personal loans, provided rate and schedule are fixed.

Monthly vs quarterly payments?

Monthly = 12 payments/year; quarterly = 4. Fewer payments tend to accrue more interest between payments.

Is my data private?

100% client-side—nothing is uploaded.

5 Fun Facts about Loans & Amortization

Front-loaded interest

On a typical mortgage, month 1 can be 70%+ interest—by halfway, most of each payment finally hits principal.

Payment mix

One extra a year is huge

Adding one extra monthly payment per year on a 30-year loan can chop ~4–5 years off and save tens of thousands in interest.

Prepay power

Biweekly ≈ 13 payments

Biweekly schedules sneak in 26 half-payments (13 full payments) a year, acting like a built-in prepayment plan.

Timing hack

APR vs APY gap

Loans quote APR (simple), but interest accrues between payments. Effective cost is higher because of compounding.

Real cost

Refi break-even is mathable

Divide refi costs by monthly savings to estimate break-even months—handy before jumping at a lower rate.

Refi check