Personal Loan Calculator

What this Personal Loan Calculator does

It calculates the payment and true cost of any fixed-rate consumer loan: personal, auto, home-improvement, or general-purpose financing. From the amount, interest rate, term, and any fees you enter, you get the periodic payment, total interest, the net amount you actually receive after fees are deducted, and the APR — the number the Truth in Lending Act (TILA) requires lenders to disclose, and the one you should use to compare offers from different lenders on an apples-to-apples basis.

The formula: payment and APR

The payment uses the standard fully-amortizing loan formula (the same one behind nearly every fixed-rate loan and mortgage in the US):

Where C is the loan amount, i is the interest rate per period, and nis the total number of payments. The APR is solved the other way around: it's the annualized rate that makes the net amount you actually receive (the loan amount minus fees) equal to the present value of every scheduled payment — the “actuarial method” Regulation Z sets out for TILA disclosures, so it reflects the loan's full financial cost, not just the stated interest rate.

A worked example

A $15,000 loan at 9.5% interest over 5 years (60 monthly payments) works out to about $315/month. Over the life of the loan you'd pay roughly $18,900 in total, of which about $3,900 is interest. Add a $300origination fee and two things change: you only receive $14,700 up front even though you still owe and repay the full $15,000, and the APR climbs above the 9.5% interest rate — even though the monthly payment itself doesn't move at all.

Common mistakes when taking out a loan

• Comparing only the monthly payment: two loans with the same payment can have very different terms and interest rates, and therefore very different total costs.
• Shopping by interest rate instead of APR: the lowest advertised rate isn't always the cheapest loan once origination and underwriting fees are factored in — the APR is the number federal law requires for a fair comparison.
• Not reading the fine print on fees: beyond origination and underwriting fees, some loans bundle optional payment-protection insurance that raises the real APR without changing the advertised payment.
• Financing a fast-depreciating purchase over too long a term: if the loan outlasts the useful life of what it paid for, you can end up paying interest on something you no longer use.
• Ignoring the option to pay it off early: if you might come into extra cash later, check whether the loan allows extra payments without a prepayment penalty before you sign — most loans originated after 2014 do.
• Borrowing more than you need “just in case”: an extra cushion sounds reasonable, but every dollar you finance accrues interest for the life of the loan, whether you end up using it or not.

Frequently asked questions

What actually moves this number

Specific levers, and roughly what each one is worth. Not “save more” — the things that change the figure above by an amount you can measure.

• Prequalify with three or four lenders in one week

  Most prequalifications use a soft pull and do not touch your score at all, and hard inquiries for the same loan type inside a short window count as one. On $15,000, a two-point rate difference is roughly $900 over three years.

• Compare APR, then look at the gap

  A 10% rate with a 10.2% APR is nearly fee-free. The same 10% rate with a 13.5% APR is carrying a large origination fee, usually deducted from the disbursement. On short terms a higher-rate no-fee loan frequently costs less overall.

• Take the shortest term you can service

  $15,000 at 11% costs about $2,676 in interest over 36 months and about $5,592 over 72. Same money, $2,916 more expensive, for a payment $205 lower. If only the long term is affordable, that is information about the purchase, not about the loan.

• Decline the insurance at signing

  Credit life and disability products are sold at the moment you are committed and no longer comparing, and the premium is often financed into the loan so you pay interest on it. Declining does not affect approval — if a lender implies it does, shop elsewhere.

What this calculator does not cover

Every calculator simplifies, and the useful thing is knowing exactly where. These are the specific gaps between this estimate and your real situation:

• It calculates from the interest rate, not the APR. If the loan carries an origination fee, your true cost is higher than the payment schedule shows — compare offers by APR.
• Origination fees are commonly deducted from the disbursement, so a $10,000 loan with a 5% fee puts $9,500 in your account while you owe and pay interest on $10,000.
• It does not model optional add-ons sold at signing. Credit life and disability products are frequently financed into the loan, so you pay interest on the premium as well.
• It assumes every payment is made on time. Late fees and any penalty rate in the contract are outside the schedule.

For anything that turns on an exact figure, use the primary sources below or a qualified professional. How these limits are decided and disclosed is described in the editorial standards.