Loan Calculator

Calculate your monthly payment, total interest, and see a full amortization breakdown for any loan - personal, auto, mortgage, or student.

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See how extra payments cut your total interest
USD - calculations use standard US amortization (fixed-rate, monthly compounding)
Monthly Payment
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Total Interest Paid
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Total Amount Paid
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Principal + interest
Payoff Date
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Principal Interest
Disclaimer: These results are estimates for informational and educational purposes only. They do not constitute financial, lending, or legal advice. Actual loan terms, payments, and interest may differ from lender to lender. Full disclaimer ->
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How to understand the loan result

This calculator estimates fixed-payment loan costs, including monthly payment, total interest, and amortization. It is useful for comparing loan terms because a lower payment can still cost more when the term is longer or the APR is higher.

Formula and assumptions

The calculator uses the standard amortization formula for fixed-rate loans. Each payment covers interest first, then principal. As the balance falls, less interest accrues and more of the payment reduces principal. Extra payments are modeled as additional principal reduction.

Example

A five-year loan may have a lower monthly payment than a three-year loan, but it usually costs more total interest. The right choice depends on cash flow, APR, emergency savings, and whether the lower payment creates room for other high-priority financial goals.

Common mistakes

  • Choosing the lowest payment without comparing total interest.
  • Ignoring origination fees or APR differences.
  • Making extra payments without confirming they apply to principal.

How to interpret your result

The monthly payment tells you cash-flow impact. Total interest tells you the cost of borrowing. The amortization schedule shows why early payments feel slow: more of the payment goes to interest when the balance is highest.

What to test next

Compare at least two terms and one extra-payment scenario. A shorter term can save interest but may reduce monthly flexibility. An extra-payment plan can create a middle path if the lender applies extra money to principal.

For more context, read APR vs interest rate and how extra loan payments save interest.

Frequently Asked Questions

How is a monthly loan payment calculated?
Monthly payment uses the standard amortization formula: M = P x [r(1+r)^n] / [(1+r)^n - 1], where P is the principal, r is the monthly interest rate (APR / 12), and n is the total number of payments. This produces a fixed payment that covers both interest and principal each month, with the split shifting toward more principal over time.
What is an amortization schedule?
An amortization schedule breaks down each payment into how much goes toward interest vs. principal. Early in the loan, most of your payment covers interest. As your balance shrinks, more goes toward principal. The year-by-year table in this calculator shows your running balance and cumulative costs so you can see the full picture.
Does a shorter loan term always save money?
Yes - a shorter term means you pay interest for fewer months, dramatically reducing total interest. A $20,000 loan at 8% APR over 3 years costs ~$1,900 in interest; over 6 years it's ~$4,000 - more than double. The trade-off is a higher monthly payment. Use this calculator to find the term that balances monthly affordability and total cost.
What is APR vs. interest rate?
The interest rate is the base cost of borrowing. APR (Annual Percentage Rate) includes the interest rate plus origination fees and other charges, making it the true cost of the loan. Always compare loans by APR rather than the stated interest rate. This calculator uses APR for accurate results. If you're using a loan to consolidate credit card debt, compare the loan APR directly against your card's APR to confirm you'll actually save money.

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