Free Amortization Calculator with Extra Payments

Use our free loan amortization calculator to compute your monthly payments, total interest cost, and a detailed amortization schedule — with support for extra payments, bi-weekly frequency, and any loan type.

Loan Details

$
Years and additional months

Payment Summary

$1,342.05
Monthly Payment
$233,139.46
Total Interest
$483,139.46
Total Amount
360
Total Payments

Payment Breakdown

Principal $250,000.00
Interest $233,139.46
Total $483,139.46
Principal 51%
Interest 49%

Amortization Schedule

Payment # Date Payment Principal Interest Balance
1 Jan 2025 $1,342.05 $404.55 $937.50 $249,595.45
2 Feb 2025 $1,342.05 $406.07 $935.98 $249,189.38
3 Mar 2025 $1,342.05 $407.59 $934.46 $248,781.79

How to Use This Amortization Calculator

Follow these four steps to calculate your loan repayment schedule and understand your total interest costs.

1

Enter Loan Details

Input loan amount, interest rate, loan term, and payment frequency for precise results.

2

Calculate Payments

The calculator instantly determines your monthly payment, total interest, and full amortization schedule.

3

Review Schedule

View each payment’s principal and interest breakdown in an easy-to-read amortization table.

4

Save Results

Download or print your amortization schedule for recordkeeping and future planning.

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Understanding Your Amortization Results

Amortization refers to repaying a loan over time through equal payments that include both principal and interest. Early payments are mostly interest, while later ones apply more toward principal.

Key Terms

Principal

The original amount borrowed, reduced with each payment.

Interest

The cost of borrowing, based on your outstanding balance.

Term

The total duration of the loan, usually in years or months.

APR

Annual Percentage Rate - the yearly cost of the loan including interest and fees.

Pro Tip

Use the Exact Interest Rate

Always input the correct annual percentage rate (APR) from your lender.

Consider Extra Payments

Making extra principal payments can lower interest costs and shorten the loan term.

Compare Frequencies

Try bi-weekly payments to save thousands in interest over time.

Review Total Costs

Remember: the total loan cost includes both principal and total interest paid.

Payment Breakdown Over Time

Early Payments

80% Interest, 20% Principal

Mid-Term Payments

50% Interest, 50% Principal

Final Payments

20% Interest, 80% Principal

Why It Matters

Understanding amortization helps you plan your budget, estimate interest costs, and identify opportunities to pay off loans faster.


Best Practices

Make additional principal payments to reduce total interest.

Consider switching to bi-weekly payments to shorten your term.

Review refinancing options if you can secure a lower rate.

The Formula Explained

Curious how the calculator works? Here's how to calculate loan amortization manually using the standard formula.

The Amortization Payment Formula

P = [r × PV] ÷ [1 − (1 + r)−n]

  • P = Periodic payment amount (e.g., your monthly payment)
  • r = Periodic interest rate = Annual rate ÷ 12 (for monthly payments)
  • PV = Present value, or the original loan amount (principal)
  • n = Total number of payments (loan term in years × 12 for monthly)

Worked Example: $350,000 Mortgage at 6.5% for 30 Years

Let's walk through the calculation step by step so you can see exactly how each number is derived.

  1. Step 1 — Find your periodic interest rate (r):
    Annual rate = 6.5%, so monthly rate = 6.5% ÷ 12 = 0.5417% (or 0.005417 as a decimal).
  2. Step 2 — Count your total payments (n):
    30 years × 12 months = 360 payments.
  3. Step 3 — Plug into the formula:
    P = [0.005417 × 350,000] ÷ [1 − (1 + 0.005417)−360]
    P = 1,895.83 ÷ [1 − (1.005417)−360]
    P = 1,895.83 ÷ 0.855
    P ≈ $2,212.24 per month
  4. Step 4 — Calculate total interest:
    Total paid = $2,212.24 × 360 = $796,406 | Total interest = $796,406 − $350,000 = $446,406

That means on a $350,000 home loan at 6.5%, you pay more than $446,000 in interest over 30 years — more than the loan itself. This is why early payoff strategies and extra payments make such a significant difference.

Common Use Cases & Tips

Real-world scenarios where an amortization calculator helps you make smarter borrowing decisions.

🏠 Scenario 1: 30-Year Home Mortgage

You're buying a home for $400,000 with a $50,000 down payment, leaving a $350,000 loan at 6.5% for 30 years. Your monthly payment comes to roughly $2,212. Over the full term, you'll pay about $446,000 in interest — more than the original loan amount. Running these numbers in the calculator before you sign helps you decide whether a 15-year term at a slightly higher monthly payment might save you $200,000+ in interest over the life of the loan.

🚗 Scenario 2: Auto Loan Comparison

You're financing a $35,000 car. Dealer A offers 5.9% for 60 months; dealer B offers 4.9% for 72 months. The 72-month loan has lower monthly payments ($558 vs. $675), but the total interest paid is $2,200 higher because of the longer loan term. Use this calculator to compare total cost — not just monthly payment — so you choose the deal that actually saves money.

💳 Scenario 3: Personal Loan Payoff Planning

You took out a $20,000 personal loan at 9.5% over 5 years. Monthly payments are $420. By making an extra $100 payment each month toward the principal balance, you can pay off the loan about 10 months early and save approximately $900 in interest charges. The amortization schedule shows you exactly which months those savings kick in.

🔄 Scenario 4: Bi-Weekly Payment Strategy

Switching your $300,000 mortgage at 7% from monthly to bi-weekly payments is one of the simplest debt-reduction moves you can make. Instead of 12 monthly payments, you make 26 half-payments per year — equivalent to one extra full payment annually. This alone can cut roughly 4–5 years off a 30-year mortgage and save more than $50,000 in total interest, all without any dramatic change to your cash flow.

🏡 Scenario 5: Student Loan Repayment (California & Texas)

Borrowers in high-cost states like California often carry larger student loan balances — sometimes $60,000 or more for a 4-year degree at a UC campus. Texas borrowers refinancing private student loans into a 10-year fixed loan at 6% can use this amortization calculator to compare standard vs. accelerated payoff plans. Keep in mind: unlike mortgages, most federal student loans don't have prepayment penalties, so extra payments go straight to reducing your principal balance and total interest cost.

📊 Scenario 6: Mortgage Refinancing Decision

You currently have a $280,000 balance on a 7.25% 30-year mortgage with 22 years remaining. A lender offers you a 20-year refinance at 6.25%. Running both scenarios through the amortization calculator shows you the new monthly payment, the total interest saved over the new term, and the break-even point for the closing costs — typically $3,000–$5,000. If you plan to stay in the home past the break-even point (often 18–30 months), refinancing makes financial sense.

How Extra Payments Reduce Your Total Interest Cost

Even small additional principal payments create a compounding effect that can save you thousands and shorten your loan term significantly.

Why Extra Payments Work So Well

Each time you pay extra toward your principal, you reduce the outstanding balance that interest is calculated on. Because mortgage interest compounds monthly, a smaller balance means less interest accrues at every subsequent payment. This creates a snowball effect: your required payment stays the same, but more of it goes toward principal instead of interest.

The earlier in your loan term you make extra payments, the greater the impact — because you're cutting into the balance before it generates years of additional interest charges. A $500 extra payment made in month one of a 30-year mortgage saves far more than the same payment made in year 20.

Extra Payment Impact Table

Based on: $300,000 loan, 6.5% interest, 30-year term

Monthly Extra Years Saved Interest Saved
$0 (baseline)
$100 / month ~2.5 yrs ~$40,000
$250 / month ~5 yrs ~$80,000
$500 / month ~8 yrs ~$120,000
Bi-weekly switch ~4.5 yrs ~$60,000

3 Smart Extra-Payment Strategies

1
Round up your monthly payment. If your required payment is $1,342, round up to $1,400 or $1,500 each month. The extra $58–$158 goes directly to principal. Over a 30-year loan, this habit can shave 2–3 years off your loan term with virtually no change to your lifestyle.
2
Apply annual windfalls to principal. Tax refunds, work bonuses, or inheritance money applied as a one-time lump-sum payment can eliminate years of future interest instantly. A single $5,000 lump-sum payment in year one of a $250,000 mortgage at 6.5% saves roughly $14,000 in total interest over the life of the loan.
3
Switch to bi-weekly payments. Ask your lender if they support bi-weekly payment processing at no fee. Paying half your monthly amount every two weeks results in 26 half-payments (13 full payments) per year. That one extra payment per year builds equity faster, reduces interest charges, and shortens a 30-year mortgage by roughly 4–5 years.

Note: Always confirm with your lender that there are no prepayment penalties before making extra principal payments. Most conventional mortgages and personal loans in the US do not carry prepayment penalties, but some auto loans and older mortgage products may.

Frequently Asked Questions

Answers to the most common questions about amortization, loan schedules, and payment strategies.

An amortization calculator helps you estimate your loan payments, total interest, and complete amortization schedule. It breaks down each payment into principal and interest portions over time.

An amortization schedule is a table showing every loan payment from start to finish. Early payments mostly cover interest, while later ones reduce more of the principal balance.

The standard amortization formula is: P = [r × PV] / [1 - (1 + r)^(-n)] Where P = payment, r = monthly interest rate, PV = loan amount, and n = total number of payments.

Yes. After entering your loan amount, interest rate, and term, the calculator automatically displays an amortization table with payment number, date, principal, interest, and remaining balance.

Absolutely. You can use it for mortgages, auto loans, personal loans, or any type of installment-based loan.

Both show how your loan is repaid, but an amortization schedule specifically details the split between principal and interest in each payment, while a repayment schedule may include extra fees or taxes.

Yes. By making additional principal payments, you reduce your outstanding balance faster, which means less interest accrues each month. For example, paying an extra $200 per month on a $300,000 loan at 6.5% can eliminate more than 5 years from your loan term and save over $60,000 in total interest charges.

Select "Bi-weekly" in the Payment Frequency dropdown. Bi-weekly payments split your monthly amount in half and apply it every two weeks. With 52 weeks in a year, this creates 26 half-payments — equivalent to 13 full monthly payments instead of 12. That one extra payment per year significantly reduces your principal balance and can shorten a 30-year mortgage by 4–5 years.

The interest rate is the base percentage charged on your principal balance. APR (Annual Percentage Rate) includes the interest rate plus lender fees, origination points, and other costs expressed as a single annual percentage. APR gives you a more complete picture of the loan's true yearly cost and is the number lenders must disclose under the Truth in Lending Act (TILA). Always compare APRs when shopping for loans.

No. All calculations are performed entirely in your browser using JavaScript. Your loan information is never sent to a server, stored, tracked, or shared with any third party. You can use this tool with complete confidence in your privacy.

As of 2026, average 30-year fixed mortgage rates in the US have generally ranged between 6% and 7%. Any rate below the current national average is considered competitive. Your specific rate depends on your credit score, down payment, loan type (conventional, FHA, VA), and lender. Borrowers with credit scores above 740 and down payments of 20%+ typically qualify for the lowest available rates.

Yes, the same amortization formula applies to any fixed-rate installment loan — mortgages, auto loans, personal loans, and student loans. The key differences are the loan term and interest rate. Auto loans typically run 24–84 months at rates from 5%–12%, while personal loans may carry rates of 8%–20%. Shorter terms mean higher monthly payments but far less total interest paid over the loan's life.