Compute the monthly payment, total interest, and full amortization schedule for any installment loan — personal, student, business, or home equity. Updated for 2026 lending rates.
Every loan is a trade. You accept a smaller future in exchange for a bigger present — the lender's job is to set a price on the difference. When that price (the APR) is fair, borrowing can be a wealth-building tool. When it isn't, the same equation runs in reverse and quietly siphons years of your work. This calculator and the explainer below exist to make sure you're on the right side of that trade.
Almost every installment loan in the U.S. — personal, student, auto, home equity, small business — uses the same payment equation:
M = P × r × (1 + r)n ÷ ((1 + r)n − 1)
M is the monthly payment, P is the principal borrowed, r is the monthly interest rate (annual APR divided by 12), and n is the total number of monthly payments. The formula is engineered so that the final payment leaves a zero balance — every month covers its own interest first, then chips at the principal. The interest portion shrinks each month and the principal portion grows, which is why the early years of any loan look like you're barely making progress.
That borrower is paying roughly 32 cents in interest for every dollar borrowed over five years. If the underlying debt being consolidated was sitting at 22% APR on credit cards, the consolidation still saved real money. If it was 8% student debt, the math doesn't work.
The practical implication: a loan advertised at 7.00% interest with $1,500 in origination fees on a $25,000 balance can carry an APR of roughly 8.4% — meaningfully higher than a competing 7.5% interest-rate loan with zero fees. Always shop on APR, never on the headline interest rate.
DTI is your total monthly debt payments (existing credit cards, student loans, auto loans, mortgage, child support, and the proposed new payment) divided by gross monthly income. Lenders use it to estimate your capacity to take on the new obligation without falling behind. Industry thresholds:
Reducing DTI before you apply — by paying off a card or two, settling small balances, or reducing the requested loan amount — often unlocks better pricing than a 10-point FICO improvement.
Most reputable U.S. online lenders, credit unions, and banks offer pre-qualification using a soft credit pull, which has no impact on your FICO. A soft pull returns an estimated rate range based on the limited information the lender can see without a hard inquiry. Shop three to five lenders this way first.
Once you've identified the best two or three offers, submit hard applications within a 14-day window. FICO bundles hard inquiries for the same loan type within that window and counts them as one inquiry — so you can compare actual rate locks without compounding the score impact.
An origination fee is what the lender charges to underwrite, process, and fund the loan. Typical ranges:
If you accept a $20,000 personal loan with a 5% origination fee, your bank deposit is $19,000 but you owe interest and principal on $20,000. APR captures this — interest rate does not. Always verify the "net proceeds" figure on the lender's disclosure form before signing.
On the same $25,000 loan at 7% APR:
Doubling the term from 3 to 7 years roughly halves the payment but more than doubles the lifetime interest. The "right" term is the shortest one whose payment doesn't crowd out essential expenses or your emergency fund contribution.
Secured loans are backed by collateral the lender can repossess if you default — a house on a mortgage, a vehicle on an auto loan, the cash inside a CD-secured personal loan. Because the lender's downside is limited, rates run 2 to 6 points lower than equivalent unsecured options. Unsecured loans (most personal loans, credit cards, federal student loans) have no collateral; rates and approval bars are higher to compensate.
The math is straightforward: if you have an asset you don't mind temporarily encumbering, a secured loan almost always saves money. The trade-off is that defaulting puts the collateral at risk, so secured borrowing is only appropriate when the payment is comfortably affordable.
A loan creates value when the cash unlocks something that returns more than its cost.
It's the algebraic solution to "find the M that makes the present value of an annuity of M payments at rate r over n periods equal exactly to P." Every fixed-rate fully-amortizing loan in the U.S. consumer market uses it, which is why payments quoted by different lenders for the same principal, APR, and term match to the penny.
FICO 740 and above generally accesses lenders' advertised "as low as" rates. The 700 to 739 band typically pays 1 to 2 points more. Below 660, most prime online lenders decline; credit unions and community banks become the next option.
Pre-qualification is a soft pull with no impact. Submitting a formal application is a hard pull and typically dings the score by 5 to 10 points for a few months. Multiple hard pulls of the same loan type within 14 days are counted as one by FICO, so shopping responsibly is safe.
Loan stacking is opening multiple personal loans within a short window — often a sign of cash-flow stress. Modern lenders share borrowing data in near real time and will decline or reprice if they see another loan funded within the past 30 to 90 days.
Yes. The process is identical to a new application; you take the new loan's proceeds, pay off the old loan, and continue with the new (typically lower) APR. The break-even on refinancing is usually 12 to 18 months from origination, after you've established a payment history and ideally improved your credit profile.
Generally no — personal-use loan interest is not deductible on Schedule A. Mortgage interest (within IRS limits), student loan interest (up to $2,500 a year for qualifying borrowers), and business-use loan interest have specific deductibility rules; consult a tax professional for your situation.
Most lenders charge a late fee of $15 to $39 if a payment is more than 10 to 15 days past due, and report the delinquency to credit bureaus once it reaches 30 days past due. A single 30-day late can drop a 760 FICO by 60 to 110 points and stays on your credit report for seven years.
The amortization formula is universal, so the math works globally. What can differ is how rates are quoted (some countries use annual flat rate, which inflates the effective cost), whether origination fees are included in APR, and whether interest accrues daily versus monthly. Confirm the local disclosure standard before assuming the result matches your lender's number to the cent.
Editorial note: This calculator and content are educational and do not constitute personalized financial or legal advice. Loan terms, APR ranges, and fees vary by lender, state, and borrower profile. Always review the Truth in Lending Act disclosure for any loan offer before signing. Last reviewed by Ellen Karuthers, MBA, on February 12, 2026.