APR Calculator

How to use

1. 1Pick a calculator mode. Rate plus fees is for shopping new loan offers, Payment plus fees is for reverse-engineering an APR from a fixed monthly payment, and Compare offers ranks two loans side by side.
2. 2Click a common loan preset (30 year mortgage, 15 year mortgage, 5 year auto loan, 3 year personal loan, FHA 30 year) to seed realistic inputs, or type your own values.
3. 3Enter the loan amount, the nominal annual rate or the monthly payment, the term as years and optional extra months, and the prepaid finance charges as a flat fee amount and a points percentage.
4. 4Read the APR, the amount financed, the total finance charge, and the breakdown rows. The APR is always at least as high as the nominal rate, and the gap grows with fees and points.
5. 5Click Copy summary to grab a one-line description with every input and the resulting APR, ready to paste into a lender comparison email, a spreadsheet, or a chat thread.

About this tool

APR Calculator computes the true Annual Percentage Rate of a closed-end installment loan, which is the standardized comparison rate disclosed under the US Truth in Lending Act (Regulation Z) and equivalent rules in Canada, the UK, the EU, and Australia. The nominal interest rate on a loan note tells you only how interest accrues on the balance; the APR rolls in the prepaid finance charges (origination fees, broker fees, document fees, and points) so two loans with the same headline rate but different closing costs can be compared apples to apples. Rate plus fees mode takes the loan amount, the nominal annual rate, the term, and any fees and discount points, then computes the monthly payment with the standard amortization formula and solves for the periodic rate r that discounts the resulting payment stream back to the amount financed (the loan amount minus prepaid finance charges) using Newton-Raphson with a bisection fallback to guarantee convergence. Payment plus fees mode skips straight to the solver: enter the actual monthly payment a lender quoted, the term, the loan amount, and the fees, and the tool returns the APR implied by that payment plan. Compare offers mode runs the calculation twice on two offers side by side, highlights the lower-APR offer, and reports the difference in percentage points, which is the right number to look at when shopping mortgages, refinancing, or comparing dealer auto loans against credit union offers. Each calculation reports the amount financed (loan amount minus prepaid finance charge), the total of payments, the total finance charge (interest plus fees), the points cost in dollars, and the number of solver iterations it took to converge, so the math is auditable. Common presets seed realistic inputs for a 30 year mortgage with one point, a 15 year mortgage with half a point, a 5 year auto loan with a flat fee, a 3 year personal loan with an origination percentage, and an FHA 30 year loan with upfront mortgage insurance, switch the currency between US dollar, euro, British pound, Canadian dollar, Australian dollar, Japanese yen, Indian rupee, and Turkish lira, and copy a one-line summary with every input and the resulting APR for a chat, email, or spreadsheet. Useful for comparing mortgage Loan Estimates, choosing between a low-rate-high-fee offer and a high-rate-low-fee offer, sanity-checking a dealer auto loan quote, understanding the true cost of an origination-fee personal loan, computing the effective rate of a buydown, and verifying the APR the lender printed on your Closing Disclosure. Lenders may define which charges count as prepaid finance charges slightly differently under their local rules, so always confirm with the official Loan Estimate or Closing Disclosure before signing. Everything runs locally in your browser; loan amounts, rates, and fees stay on your device.

Free to use. Works in your browser. No signup, no login.