APR explained: compare loans the way lenders do
The APR calculator helps you judge the true cost of borrowing by folding relevant fees into one comparable rate. Advertised interest rates are useful for estimating payments, but they can conceal meaningful differences in lender fees, points, and required insurance that change your total outlay. APR converts those moving parts into a single annualized percentage, so two loans with different structures can be compared fairly. It’s especially helpful when the fees are front-loaded (points) or when a slightly lower note rate tempts you to ignore breakeven timing.
In plain terms, APR answers the question: “Given what I actually receive today and what I must pay back over time, what rate would make those cash flows break even?” Because it’s an IRR, APR naturally accounts for payment timing and compounding. That means the same rate can imply different dollar costs if the term changes—paying interest for 15 years is fundamentally different from 30. When you see a low APR, you’re generally looking at either lower fees, a lower note rate, or a shorter horizon in which fees are amortized.
Best uses: compare mortgage offers with different points, evaluate personal loans that bundle origination fees, or weigh the impact of PMI while your down payment is below conventional thresholds. Limitations: APR does not predict your future behavior (refinances, early payoff), and not every third-party cost is always included. For bigger decisions, run a few scenarios and note the breakeven—how long until the cheaper monthly payment repays the upfront cost.
Educational estimates only. APR treatment of fees can vary by jurisdiction and loan type. Confirm disclosures with your lender.