Free Online APR Calculator

What the APR calculator shows

A loan advert usually names one number: "0% interest", "from 1% a day" or "24% a year". But a loan costs more than its interest. There may be an arrangement fee, a monthly account or service fee, required insurance, a notary, and on fast loans a fee that is withheld before the money ever reaches your card. This calculator turns all of that into one yearly rate, so offers built in different ways can be compared fairly.

The headline number is the effective annual rate, the figure EU consumer credit rules call the annual percentage rate of charge. The calculator labels it APRC to keep it apart from the American APR, which is calculated differently. Next to it you get the nominal APR as US lenders quote it, the total cost of credit (what you pay on top of the loan), the total amount payable and the amount you actually receive after any fee withheld at payout.

There are two modes. The first is for loans with monthly payments: personal loans, store instalment plans, car loans. The second is for short loans repaid in one payment after a few days or weeks, the typical payday loan. Everything is calculated in your browser, and nothing you enter is sent anywhere.

In this guide:

• how to fill in both modes and how to read the results;
• how the effective annual rate is calculated and how it differs from a nominal APR;
• which costs go into the rate and which do not;
• how a "0%" instalment becomes a loan at 36% a year;
• short loans, daily rates and why yearly rates reach thousands of percent;
• how to compare offers, a reference table, three worked examples and the most common mistakes.

How to use the APR calculator

First pick the mode under Loan type: Monthly payments or Repaid in days. The Loan amount field is shared by both. It is the total amount of credit in the contract, before any fee is withheld. If the lender promises $30,000 and $29,400 arrives in your account, enter 30,000 and the difference as a fee. The currency switch above the fields only changes the label, not the calculation; the examples in this guide use dollars.

A loan with monthly payments

1. Term. The number of months. The Common terms chips fill in 6, 12, 24 or 36 months; type any other number up to 360.
2. Payments. Choose how you know the schedule. From the interest rate: enter the Interest rate (per year) from the contract and the Repayment scheme, either Annuity (the same payment every month) or Equal principal (the loan repaid in equal parts plus interest on what is left). From the monthly payment: enter what you pay each month, for offers that quote only "from 99 a month" and no rate.
3. Upfront fee. Charged or withheld when the loan is paid out. The switch next to it sets the fee as an amount or as a percentage of the loan amount.
4. Monthly fee. Charged every month, as a percentage of the original loan amount or as a fixed amount. The default is 1.5%, the shape of a typical "0%" instalment plan.
5. Other costs under More options. Up to ten rows, each with a name, an amount, when it is Paid (At payout, Every month or Every year) and the Include in the rate checkbox. A yearly cost such as insurance is placed on the payout date and then every 12 months while the loan runs.

A loan repaid in days

1. Term. In days, from 1 to 365; the chips fill in 7, 14, 30 or 60 days.
2. Interest per day. The rate from the contract, such as 1 or 0.8. Interest is charged on the whole loan amount for every day.
3. Fee. One fee, as an amount or a percentage, and Fee is paid: Withheld at payout or With the repayment.

The list of other costs is not used in this mode. A short loan has one fee and a daily interest charge, and those are what the calculator prices.

Reading the results

The headline is the Effective annual rate (APRC). Below it a bar splits the total amount payable into the Amount you receive and the Total cost of credit. The figures underneath show the Nominal APR (US method), the Total amount payable and, when you work from the monthly payment, the Interest rate implied by the payments. A cost you leave out of the rate appears as Costs outside the rate. For a loan with monthly payments, the Chart tab shows how much of each payment repays the loan and how much is interest and fees, and the Payment schedule tab lists every month in a table. Pin to compare keeps the current result; change the terms and the difference appears next to the rate in percentage points.

How the effective annual rate is calculated

The idea is the same in every rule book that uses an effective rate. The money you actually receive is set equal to all your future payments, each discounted at the rate being looked for. Whatever you pay on the day of payout, such as an arrangement fee or the first insurance premium, is taken off the loan amount first, because you never had the use of it.

Amount received = Σ Payment_t ÷ (1 + r)^t, for months t = 1 … n
Effective annual rate (APRC) = (1 + r)^12 − 1
Nominal APR (US method) = 12 × r

Payment_t = everything you pay in month t: principal, interest, fees, included costs
r = the monthly rate that makes both sides equal

There is no closed formula for r. It is found numerically, the same way a spreadsheet's XIRR function finds a rate of return. The EU annex that sets out the equation measures time in years and fractions of a year, and lets a year be counted as 365 days, 52 weeks or 12 equal months, with an equal month of 30.41666 days. The calculator uses equal months, because it does not know your actual payment dates. A lender that counts the real dates, as XIRR does with a 365-day year, may show a slightly different figure. More on how XIRR works is in the guide to the annualized return calculator.

How large is the difference? For example 2 below ($9,700 received, twelve payments of $900) the calculator gives 22.31%. XIRR with the payout on 15 January 2026 and payments on the 15th of each month gives 22.42%; with the payout on 10 March, 22.18%. For the default instalment plan the same January dates give 36.94% against the calculator's 36.76%. A gap of a few tenths of a point is normal, and its sign depends on the dates. On short or expensive loans it grows: the same plan over three months gives 30.35% in the calculator and from 29.88% to 31.65% with XIRR, depending on the payout day. For comparison, US rules treat a disclosed APR as accurate if it is within one eighth of a percentage point for a regular loan and a quarter of a point for an irregular one. If your figure is further off than the dates explain, the lender most likely counted a cost you did not enter.

Why turn everything into a compounded yearly rate at all? Because money has a time value: a payment made earlier costs you more than the same payment made later. That principle, and the compounding behind it, is explained in the article on compound interest and the time value of money.

Nominal vs effective: the US APR and the EU APRC

The rate in a loan contract is a nominal interest rate. It sets how much interest is charged on the balance, but says nothing about fees. The effective annual rate counts everything. Between the two sits a third number that English-language sources use all the time: the American APR.

In the US, Regulation Z describes the annual percentage rate as a measure of the cost of credit, expressed as a yearly rate, that relates the amount and timing of value you receive to the amount and timing of your payments. So it counts fees and timing, like the effective rate. But its Appendix J turns the rate per period into a yearly one by simple multiplication: the rate for one period times the number of periods in a year, 12 for a monthly loan and 365 for a loan counted in days. There is no compounding. The calculator shows this number as Nominal APR (US method).

EU rules compound. The Consumer Credit Directive 2008/48/EC defines the annual percentage rate of charge as the total cost of credit expressed as an annual percentage of the total amount of credit, and its successor, Directive (EU) 2023/2225, keeps that definition and the same equation. The result is always higher than the US figure for the same loan, and the gap grows with the rate.

The first row shows that even without a single fee the effective rate of 26.82% is above the 24% in the contract, because interest is charged monthly, not once a year. So compare effective with effective and nominal with nominal. An offer at "24% a year" and an offer with a 26.82% effective rate can be the very same loan.

The EU directive changes on 20 November 2026. From that date Directive 2023/2225 applies and 2008/48/EC is repealed, although agreements already running on that date stay, with a few exceptions, under the old rules until they end. For the APR, the definition and the equation stay the same; the new directive abbreviates the annual percentage rate of charge as APR.

Which costs go into the rate

The answer differs a little between rule books, but the core is shared.

• Interest always counts.
• The lender's fees count: arrangement or origination fees, monthly account or service fees, fees for paperwork.
• Costs paid to others count when you must pay them to get the credit. Directive 2023/2225 names commissions, taxes and fees, and ancillary services such as insurance when they are compulsory to obtain the credit or to obtain it on the terms marketed. In the US, Regulation Z's finance charge includes third-party charges the lender requires, points and loan fees, appraisal and credit-report fees, insurance that protects the lender, and credit life, accident and health insurance, with exceptions set out in the rule.

What does not count:

• Penalties and late fees. They arise only if you break the contract. Regulation Z leaves late and default charges out of the finance charge, and the calculator never puts them in the rate.
• The price of what you buy. A phone bought on an instalment plan is not a cost of credit; the fee for setting up the plan is.
• Notary fees in the EU. Both EU directives leave notarial costs out of the total cost of credit. In the US, bona fide notary, title, document-preparation, appraisal and credit-report fees are left out of the finance charge on real-estate loans.
• US application fees charged to every applicant, whether or not they get the loan.

In the calculator every row under Other costs has an Include in the rate checkbox, ticked by default, because a cost you have to pay for the loan belongs in its price. Untick it for notary fees to match the EU's legal rate, to see how much one cost alone raises the rate, or when you would buy the service anyway. Excluded costs do not disappear: the calculator shows them as Costs outside the rate.

A yearly cost shows the effect clearly. Take $200,000 over 24 months at 18% with an annuity payment of $9,984.82, plus insurance of $1,500 a year. Included, it is paid at payout and again after 12 months, and the effective rate is 21.25%. Excluded, the rate is the loan's own 19.56% and $3,000 sits outside the rate.

"0%" offers and monthly fees

The most common way to make a zero-interest loan expensive is a monthly fee on the original amount. Take the calculator's default: $3,000 over 12 months at 0% with a 1.5% monthly fee. The principal is $250 a month and the fee $45, so you pay $295 a month. Over the year you hand over $3,540, so the credit costs $540, or 18% of the amount.

Why, then, is the effective rate 36.76% and not 18%? Because the $45 is charged on the full $3,000 every month while the debt melts away. In the last month you owe only $250 and still pay the same fee. On average over the year you have the use of about half the money, so every dollar you really borrow costs roughly twice as much. The equation captures this by weighting each payment by its timing.

The term barely changes the rate of such a plan, but it changes the cost a lot. With the same 1.5% monthly fee on $3,000:

• 6 months: effective rate 34.79%, cost $270;
• 12 months: 36.76%, cost $540;
• 24 months: 36.42%, cost $1,080;
• 36 months: 35.27%, cost $1,620.

If the shop also charges a 2% arrangement fee, $2,940 reaches you or the seller, the cost rises to $600 and the effective rate to 42.24%. A 2.5% monthly fee on $100,000 gives 65.48%, and "0.01% a year" with a 3.5% monthly fee gives 97.97%.

Short loans: days mode and daily rates

A loan for a few days is priced by the day, so the calculator has a separate mode for it. You get the money once, minus any fee withheld, and repay once, the amount plus daily interest plus any fee charged at repayment. With one payment out and one payment back, the equation has a direct solution.

Effective annual rate = (Repayment ÷ Amount received)^(365 ÷ days) − 1
Nominal APR (US method) = 365 × ((Repayment ÷ Amount received)^(1 ÷ days) − 1)

$5,000 for 15 days at 1% a day, $250 fee withheld:
(5,750 ÷ 4,750)^(365 ÷ 15) − 1 = 10,348.16%

When the fee is paid matters. A $250 fee withheld at payout leaves you $4,750 to use; the same fee paid with the repayment leaves you the full $5,000. The cost is $1,000 either way, but the effective rate is 10,348.16% in the first case and 8,347.8% in the second. A simple cost-per-day figure, $1,000 ÷ $5,000 ÷ 15 days = 1.33% a day, cannot see that difference; the effective rate can.

Why the yearly rate runs into thousands of percent

Borrowing $10,000 for 30 days at 1% a day costs $3,000. The nominal APR is 320.61%: the daily rate of 0.8784% at which $10,000 grows to $13,000 in 30 days of daily compounding, times 365. The effective rate is 2,333.95%, because it imagines you borrowing and repaying on those terms all year, each time rolling the cost into the next loan. At the same 1% a day, a 7-day loan comes to 3,305.29% and a 60-day loan to 1,644.74%. The shorter the loan, the stronger the compounding. These numbers do not mean you will pay that much in a year, but they do show the true price of money for a week or a month.

The Repaid in days mode counts such a loan by days, as it should. If you enter the same 30-day loan in the monthly mode as a one-month loan, the calculator treats the month as a twelfth of a year and shows 2,229.81% instead of 2,333.95%. For a short loan, always use the days mode.

Comparing offers: rate, APR and overpayment

Three numbers answer three different questions, and none of them replaces the others.

• The interest rate in the contract sets the interest on the balance. On its own it is only useful for loans without fees.
• The effective annual rate gives the price of the loan with every cost included and with the timing of your payments taken into account. It is the main number for choosing between offers of the same amount and term.
• The total cost of credit, what you pay on top of the loan, tells you how much money the loan takes out of your budget.

The total cost cannot be compared across different terms. A 36-month loan almost always costs more in total than a 12-month one, even at a lower rate, because you keep the money longer. And a low cost on a short loan can hide a rate in the thousands of percent. Compare offers by the effective rate, then check whether the monthly payment and the total fit your budget. The budget planner helps you see what is left each month after a new payment.

Before borrowing for anything that is not urgent, ask whether saving first would be cheaper. Even a small cash reserve keeps you away from a payday loan at thousands of percent: the article on the emergency fund explains how to build one, and the emergency fund calculator works out how much you need.

When comparing, make sure each offer is entered the same way. Use the full loan amount from the contract, include the same kinds of costs, and pin the first offer before you enter the second. The delta next to the rate then tells you, in percentage points, how much more or less the second offer costs per year.

APR at a glance

How individual costs change the rate of one and the same loan: $100,000 over 12 months at 24% a year, with an annuity payment of $9,455.96.

A $500 monthly fee adds up to $6,000 a year and raises the rate by about 13 points, while a $2,000 upfront fee raises it by 5. The reason is the same as with the "0%" plan: the fee is charged on the full amount while the debt shrinks. Without fees the repayment scheme does not change the effective rate: Equal principal gives the same 26.82%, although the total cost is lower, $13,000, because the debt is paid down faster. To see how the annuity and equal-principal schedules themselves are built, use the loan and mortgage calculator.

Worked examples

All amounts below come from the calculator, rounded the way the result shows them.

Compare examples 1 and 3: the instalment plan costs $540 over a year and the payday loan $1,000 over 15 days, but per dollar and per year the payday loan costs about 282 times as much. The size of the cost says nothing on its own about the price of a loan.

Common mistakes

• Entering the amount you receive instead of the loan amount. The Loan amount is the total credit in the contract; fees withheld at payout go in separately. Otherwise the calculator understates the rate.
• Treating a monthly fee as interest on the balance. A 1.5% monthly fee on the original amount costs far more than 18% a year on the balance: the effective rate is 36.76%.
• Comparing the total cost of loans with different terms. A longer loan almost always costs more in total. Compare the effective rate, and check the total cost separately for your budget.
• Comparing an effective rate with a nominal one. The contract rate, the US APR and the effective annual rate are three different numbers; 24% in a contract with no fees is 26.82% effective.
• Pricing a payday loan in the monthly mode. For a 30-day loan the monthly mode shows 2,229.81%, the correct days mode 2,333.95%.
• Forgetting insurance and third-party costs. If the loan is not granted without insurance, it belongs in the rate. Add it under Other costs.
• Ignoring how the fee is taken. The same fee costs more when it is withheld at payout than when it is paid with the last payment.
• Ignoring inflation. On a long loan with fixed payments, inflation slowly reduces the real weight of each payment; the article on inflation and why money loses value explains the mechanism.

Limitations and next steps

The calculator prices a loan on the terms you enter and on the same assumptions as the legal APR: the contract runs its full term, every payment is made on time, and the interest rate and fees stay the same. It does not model:

• actual payment dates: every month is a twelfth of a year, so the lender's figure can differ by a few tenths of a point, and by a point or more on a short or expensive loan;
• variable rates, credit lines and credit cards with changing balances and grace periods;
• early repayment, missed payments, penalties and late fees;
• loans paid out in several parts;
• extra costs in the days mode beyond its one fee;
• any national cap on rates or costs.

Use the result as a check on the lender's own disclosure, not as a replacement for it. If the numbers differ by more than the payment dates explain (run XIRR on the real dates to check), ask which costs the lender counted. If you plan to repay early, enter a shorter term and pin the comparison to see what you would save, then check the contract for early repayment fees.

If the loan is for a home or a car, work out the schedule with the loan and mortgage calculator, then bring the fees from the offer here to see the full yearly price. And if the loan is meant to bridge a gap you could have saved for, the compound interest article shows how quickly the same money grows when it works for you rather than against you.