Loan Calculator
Estimate monthly payment, total interest, and total cost for a fixed-rate loan.
About this tool
Enter a loan amount, annual interest rate, and term (in years or months) to estimate the monthly payment using the standard fixed-rate amortization formula - the same formula lenders use to calculate a level payment that pays off both principal and interest by the end of the term. Alongside the monthly payment, the tool shows total interest paid over the life of the loan and the total amount paid (principal plus interest combined), so you can see the full cost picture, not just the monthly number. This is explicitly an estimate for informational purposes, not financial advice: it calculates a standard fixed-rate amortization and does not account for fees, closing costs, taxes, insurance, or a specific lender’s actual terms, all of which can meaningfully change what you’d really pay. Useful for getting a ballpark sense of affordability before talking to a lender, not for finalizing a real loan decision. Runs entirely client-side.
Frequently asked questions
It uses the standard fixed-rate amortization formula: M = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan amount, r is the monthly interest rate (annual rate divided by 12), and n is the total number of monthly payments. This is the same formula used to calculate a level payment - one that stays the same every month - for a traditional fixed-rate loan like most auto loans and standard mortgages.
Those costs vary enormously by lender, loan type, and location - an origination fee, property tax escrow, or required insurance premium isn’t part of the core amortization math, and folding in a guessed number would make the estimate less accurate, not more. This calculator intentionally sticks to the loan itself (principal and interest) so the number it gives you is at least mathematically exact for that piece, with the disclaimer that it’s not your full real-world cost.
Treat it as a starting-point estimate to get a general sense of affordability, not as a substitute for an actual loan quote from a lender or advice from a financial professional. Real loan offers include fees, may have variable rather than fixed rates, and depend on factors like your credit profile that this calculator has no way to account for.
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