Effective Annual Percentage Rate (APR) Math Tool
Expose hidden mortgage origination fees and padded discount points by mathematically combining them into the true federal APR signature.
Input your parameters to generate the True APR / Effective Annual Rate Calculator results.
How to Use This Calculator
Get accurate results in seconds by following these simple steps.
Enter Note Rate
Input the quoted promissory note interest rate from your lender.
Add All Fees
Enter discount points, origination fees, and any other prepaid finance charges.
Reveal True APR
See the federally mandated APR that exposes the total cost of borrowing.
Why Use This Tool?
Hidden Fee Detection
Expose lender fees disguised behind attractive advertised interest rates.
TILA Compliance
Uses the same Truth-in-Lending methodology required by federal regulators.
Lender Comparison
Compare lenders by APR instead of note rate for a dramatically more honest picture.
Unveiling Truth in Lending
The 'Promissory Note Rate' is the interest rate you physically sign on the federal loan agreement. It is the number the bank aggressively advertises in order to capture your lead.
The true 'Annualized Percentage Rate' (APR) is mandated by the Truth in Lending Act. It protects consumers by forcing banks to calculate essentially what the interest rate *would be* if they took all their secretive closing costs, origination padding, and discount point revenue—and shoved them mathematically inside the loan itself.
This simulator utilizes an incredibly powerful numerical solver algorithm to reverse-engineer exactly how much financial damage the lender's upfront fees are inflicting relative to their advertised baseline interest rate.
Frequently Asked Questions
Because you are paying closing costs and lender fees just to obtain the loan. The APR takes those upfront thousands of dollars, divides them mathematically over 360 months, and translates that burden straight back into a percentage to expose the reality of the banking contract.
Strictly by APR. A lender offering a 5.5% interest rate with a 6.0% APR is charging you massive, disastrous upfront fees. A lender offering a 5.75% rate with a 5.8% APR is offering an infinitely more honest, cheaper loan structuring.
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