APR Calculator: Turn Any Loan Fee Into an APR

One tool for every offer: enter the amount, the fee, and the term. Get the annualized APR.

The APR is the only number that compares offers of different sizes, fees, and terms on equal footing. Enter the amount borrowed, the flat fee the offer charges, and the term in days. The calculator returns the annualized APR, the fee restated per $100 borrowed, and the total repayment.

The defaults show the canonical payday case: a $75 fee on $500 for 14 days is 391% APR, or $15 per $100. The same $75 fee on a 31-day term is only 176% APR, which is the honest way to see that term length, not just the fee, drives the annualized number.

Two boundaries keep this tool honest. First, it prices the fee you enter; a lender’s contract can add charges the APR line in an advertisement omits, and the binding figure is the one in the disclosure you sign. Second, for covered servicemembers and dependents the Military Lending Act caps the cost at 36% APR regardless of what the calculator shows for a market offer.

Amount borrowed, $ Flat fee, $ Term in days

Annualized APR

Per $100 borrowed

Total repayment

The legal context for every state is in the rates and fees table, and the full numbers are in our APR disclosure.

Once the APRs are lined up, the honest comparison is the total of payments against your budget. The installment and slack calculators cover the payment side, and the request form prices real offers in minutes.

Frequently asked questions

What is APR in simple terms?

The cost of credit expressed as a yearly rate. The calculator takes the fee an offer charges and asks: if this fee repeated for a year at this term, what rate would that be? It is the only number that compares offers of different sizes and terms.

How do I compare a payday loan and an installment loan?

By APR, then by total cost of credit. A $75 fee on $500 for two weeks is 391% APR; a $1,300 installment at 130% APR costs $534.89 in interest over six months. The first is bigger per dollar per year, the second is bigger in total dollars.

Does the APR include every fee?

It includes the fee you enter. Lender disclosures may add origination fees, ancillary products, or returned-payment charges. The calculator is the baseline; the lender's own disclosure is the binding number.

What APR is considered high?

For context: 36% is the Military Lending Act ceiling for covered borrowers and the general benchmark for affordable credit. Most licensed payday products annualize between 390% and 660%. Between those numbers sits nearly everything this site prices.

Reviewed by Marcus Bell, Reviewer, credit counseling background. Every fee, cap, and formula on this page was checked against the published state rules.

Last reviewed: 2026-09-26