Loan Calculator Online
Work out the monthly payment, total interest and payoff of any amortized loan right in your browser. Estimates only, not financial advice.
The Loan Calculator runs entirely in your browser. The loan amount, rate and term you enter stay on your device and are never uploaded to ArrayKit. Results are estimates only, not financial advice.
Open the Amortization Calculator
About Loan Calculator
The Loan Calculator works out the monthly payment, total interest and total payoff for any fixed-rate amortized loan — a personal loan, auto loan, or any installment plan with equal monthly payments. Enter the loan amount, the annual interest rate, and the term in years or months, and it applies the standard amortization formula to spread principal and interest across every payment. You can expand a full month-by-month amortization schedule to see how much of each payment goes toward interest versus principal and how the balance declines over time. It is handy for comparing loan offers, checking a lender's numbers, or planning a payoff timeline before signing. These are estimates only, not financial advice — confirm final figures with your lender. Everything runs locally in your browser; your loan amount and rate are never uploaded.
Features
- Computes the monthly payment for any principal, rate and term
- Shows total interest paid and total amount paid over the life of the loan
- Toggle the term between years and months
- Optional full amortization schedule with interest, principal and balance per payment
- Handles a 0% interest rate as an even principal-only split
- Copy a plain-text summary of the loan payment and totals
- Clear error banner for an invalid amount, rate or term
- Runs entirely in your browser with no loan data sent anywhere
How to use the Loan Calculator
- Enter the loan amount you want to borrow
- Enter the annual interest rate (APR) as a percentage
- Enter the loan term and switch between years and months
- Read the monthly payment, total interest and total paid, and expand the schedule for a full breakdown
Example
Input
$10,000, 5% APR, 36 months
Output
Monthly payment: $299.71
Total interest: $789.52
Common errors & troubleshooting
- The monthly payment looks far too high. — Check the interest rate field — enter the annual percentage as '5' for 5%, not '0.05', which the Loan Calculator would read as 0.05% instead of 5%.
- Results show an error banner instead of a payment. — Make sure the loan amount is greater than 0 and the term is a whole number of months or years greater than 0.
- The total interest seems different from what the lender quoted. — Confirm the lender's rate is a simple annual percentage compounded monthly; loans with different compounding, fees, or a variable rate will differ from this fixed-rate estimate.
- The amortization schedule doesn't show every payment. — Long terms are capped in the on-screen table to keep it fast to scroll — the total payment count is still shown below the visible rows.
Frequently asked questions
- What does the Loan Calculator compute?
- It computes the fixed monthly payment, total interest, and total amount paid for an amortized loan, given the principal, annual interest rate and term. It also builds a full amortization schedule.
- What formula does the Loan Calculator use?
- The standard amortization formula: M = P·r·(1+r)^n / ((1+r)^n − 1), where P is the principal, r is the monthly interest rate, and n is the number of monthly payments. A 0% rate is treated as principal divided evenly by the number of payments.
- Can I enter the loan term in years instead of months?
- Yes. Switch the term toggle to Years and the Loan Calculator converts it to months automatically, or switch to Months to enter the term directly.
- Does the Loan Calculator show an amortization schedule?
- Yes. Expand the schedule to see, payment by payment, how much goes to interest, how much goes to principal, and the remaining balance.
- Is the Loan Calculator's result financial advice?
- No. The Loan Calculator produces estimates only, not financial advice. Actual payments can differ due to fees, rounding, variable rates, or a lender's specific compounding method — always confirm final numbers with your lender.
- Does the Loan Calculator send my loan amount anywhere?
- No. The Loan Calculator runs entirely in your browser. The amount, rate and term you enter stay on your device and are never uploaded to ArrayKit.
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