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Loan & Amortization Calculator

Calculate loan payments, total interest, and a complete amortization schedule.

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Please ensure all amounts use the same currency. This tool does not perform exchange rate conversion.
🔒 All loan calculations and amortization schedules are computed locally in your browser. Nothing is uploaded to Qudo servers.

Loan & Amortization Calculator

This calculator helps you estimate monthly payments, total interest, and generate a complete amortization schedule for fixed-rate loans. It supports both fixed payment and equal principal methods, extra payments, and loan fees.

How Loan Payments Are Calculated

For a fixed payment loan, each payment covers both interest and principal. The formula is: A = P × r × (1+r)^n / ((1+r)^n - 1), where P is principal, r is the periodic rate, and n is total periods. Early payments have more interest; later payments have more principal.

What Is Loan Principal?

The principal is the amount you borrow. If you add fees to the principal, the effective principal (the amount interest is calculated on) may be higher than the nominal amount.

What Is Loan Interest?

Interest is the cost of borrowing money, calculated as a percentage of the remaining balance. As you pay down the balance, the interest portion of each payment decreases.

Interest Rate vs APR

The interest rate is the cost of borrowing the principal. APR (Annual Percentage Rate) typically includes the interest rate plus some loan fees, giving a broader measure of borrowing cost. This tool uses the nominal rate you enter.

Fixed Payment vs Equal Principal

Fixed payment: each period's total is roughly the same, but early payments are mostly interest. Equal principal: each period pays the same principal amount plus interest on the remaining balance, so payments decrease over time. Equal principal usually results in less total interest.

Why Is Interest Higher at the Beginning?

Interest is calculated on the remaining balance. At the start, the balance is highest, so the interest portion is largest. As you pay down principal, the balance decreases and so does the interest.

How Extra Payments Save Interest

Extra payments go directly toward reducing principal. This lowers the remaining balance faster, reducing future interest charges and potentially shortening the loan term.

How Fees Affect Total Cost

Loan fees (application fees, origination fees, etc.) add to the total cost. If fees are added to the principal, interest is calculated on a higher amount. If deducted from disbursement, you receive less but still repay the full principal.

Why Results May Differ from Your Lender

Actual loan terms depend on your lender's specific calculation methods, compounding frequency, day count conventions, and fees. This tool provides mathematical estimates based on standard formulas.

Privacy

All calculations run locally in your browser. No loan amounts, rates, or schedules are uploaded to any server.

Limitations

  • This tool provides mathematical estimates, not loan offers, credit approvals, or legal repayment documents.
  • It does not support variable-rate loans, balloon payments, or interest-only loans.
  • It does not calculate official APR as defined by any jurisdiction.
  • Actual terms depend on your lender's policies and local regulations.
  • For formal financial decisions, consult a qualified professional.

Frequently Asked Questions

How is the monthly payment calculated?
For fixed payment: A = P × r × (1+r)^n / ((1+r)^n - 1). For equal principal: each payment = P/n + remaining balance × r.
What is the difference between fixed payment and equal principal?
Fixed payment has the same total each period (mostly interest early, mostly principal later). Equal principal has the same principal each period, so total payment decreases over time.
Why is interest higher in the early payments?
Interest is based on the remaining balance. The balance is highest at the start, so interest is highest initially.
What is the difference between interest rate and APR?
Interest rate is the cost of borrowing principal. APR typically includes some loan fees, giving a broader cost measure. This tool uses nominal rate.
How much interest can extra payments save?
Extra payments reduce the principal faster, which reduces future interest. The savings depend on the amount, timing, and remaining term.
Are extra payments always applied to principal?
Not necessarily. Some lenders may apply extra amounts to future payments. Confirm with your lender how they handle extra payments.
Can prepayment incur penalties?
Some loans have prepayment penalties. Check your loan agreement for details.
Should fees be added to the loan principal?
It depends on your agreement. Adding fees to principal means you pay interest on them. Paying separately avoids this but requires upfront cash.
Why do results differ from my lender's numbers?
Lenders may use different compounding methods, day count conventions, or rounding rules. This tool uses standard mathematical formulas.
How is a 0% interest loan calculated?
Each payment = principal ÷ number of periods. Total interest is zero.
What is the difference between bi-weekly and monthly payments?
Bi-weekly means 26 payments per year (equivalent to 13 monthly payments), which can save significant interest over time.
Does the schedule include taxes and insurance?
No. This tool calculates principal and interest only. Taxes, insurance, and other costs are not included.
Can I use different currencies?
You can change the display currency, but all amounts must use the same currency. No exchange rate conversion is performed.
Is my loan data uploaded?
No. All calculations run locally in your browser. No data leaves your device.
Can results be used as a formal loan quote?
No. This tool provides mathematical estimates based on your inputs and stated assumptions. It is not a loan offer, credit approval, or legally binding repayment document.

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All calculations are performed locally in your browser. No data is sent to servers.