InputsLive
Loan amount
$
Down payment
$
Annual interest rate
%
Loan term
yrs
Result
Monthly payment
$391.32
Total interest: $3,479.38 · Total cost: $23,479.38
Monthly payment$391.32
Total interest$3,479.38
Total cost$23,479.38
Amount financed$20,000

Fixed-rate amortized loan. Does not include fees, insurance, or taxes. Rates and terms vary by lender.

Results are estimates. Consult a professional.

How it's calculated

How the loan calculator works

A standard installment loan charges a fixed interest rate on the remaining balance and spreads repayment across equal monthly payments over the loan term. Each payment covers that month's interest first; the remainder reduces principal. Because the balance falls each month, the interest portion shrinks and the principal portion grows — this is called amortization.

r = annual_rate ÷ 12
Monthly payment = P × r × (1 + r)^n ÷ ((1 + r)^n 1)
Total interest = (monthly_payment × n) P
Total cost = monthly_payment × n
Federal Reserve: Consumer Finance Survey — installment loan structures
Example

Worked example: $20k loan at 8% over 48 months

Example: $20,000 personal loan at 8% APR, 48-month term

A borrower takes out a $20,000 personal loan at 8% APR to fund a home renovation. They choose a 48-month term to keep payments manageable while minimizing total interest compared to a longer term.

r = 0.08 ÷ 12 = 0.006667
Payment = 20,000 × 0.006667 × (1.006667)^48 ÷ ((1.006667)^48 1)
Monthly payment = $488
Total interest = ($488 × 48) $20,000 = $3,424
Total cost = $488 × 48 = $23,424
$488/mo
Monthly payment on the $20,000 loan. Total cost is $23,424 over 48 months, meaning $3,424 paid in interest for access to $20,000 today.
Quick reference

Monthly payment by loan amount, rate, and term

Use this table to quickly estimate your monthly payment. Find your loan amount, cross-reference your approximate APR, and choose the term that fits your budget.

Loan Amount6% / 36 mo8% / 48 mo10% / 60 mo12% / 60 mo
$5,000$152$122$106$111
$10,000$304$244$212$222
$15,000$456$366$319$333
$20,000$608$488$425$445
$30,000$912$732$637$667

Source: Federal Reserve Consumer Finance Survey; calculated using standard amortization formula

Practical tips

Tips for getting the best loan terms

The rate and term you're offered depend heavily on your credit profile and how you shop. Even a 1–2 percentage point difference in APR can save hundreds to thousands of dollars over a loan's life.

  • Shop at least three lenders — rates for the same borrower vary significantly between banks, credit unions, and online lenders; getting multiple quotes takes 10 minutes and can save thousands.
  • Check your credit report before applying — errors on your credit file can cost you 1–3 percentage points on your rate; dispute inaccuracies at annualcreditreport.com before any loan inquiry.
  • Choose the shortest term you can comfortably afford — a shorter term means a higher monthly payment but dramatically less total interest; use this calculator to find the sweet spot.
  • Consider a credit union — federal credit unions cap personal loan APR at 18% and often offer rates 1–3 points below traditional banks for the same credit profile.
  • Avoid prepayment penalty loans — if you plan to pay extra or refinance, make sure the loan has no prepayment penalty; those fees can erase the savings from early payoff.
Accuracy & limits

Accuracy and limitations

This calculator uses the standard amortization formula and assumes a fixed interest rate for the entire loan term. It does not account for origination fees, prepayment penalties, lender-specific rounding, or the effect of a first payment date that differs from the loan origination date. Actual lender quotes may vary slightly. For auto loans, the total cost of ownership includes insurance, maintenance, and registration fees not modelled here.

Not financial advice — consult a financial professional for your specific situation.

Glossary

Loan terms defined

The original amount borrowed, before any interest is added. Each monthly payment reduces the outstanding principal balance.
The yearly interest cost of the loan expressed as a percentage. For simple installment loans without fees, APR equals the interest rate. When fees are included, APR is higher than the stated rate.
The total number of months (or years) over which the loan is repaid. Longer terms mean lower payments but more total interest.
The gradual reduction of a loan balance through scheduled payments that cover both interest and principal. Early payments are mostly interest; later payments are mostly principal.
The cumulative cost of borrowing — all interest charges paid over the life of the loan. Equal to (monthly payment × number of payments) minus the original principal.
An upfront lender fee, typically 1%–8% of the loan amount, that raises the true cost above what the APR implies. Always check whether quoted rates include fees.
About

About this loan calculator

This calculator runs entirely in your browser — nothing you enter is sent to any server.

Browse more in our finance calculators, or explore the complete library on the free calculators page.

Questions

Frequently asked questions about the free loan calculator

A loan calculator is a free online tool that helps you standard amortized loan payment calculator. Standard amortization formula. Plug in principal, APR, and term in months. It runs entirely in your browser with instant results and no sign-up.
No — actual loan terms depend on credit, income docs, and lender underwriting. Use this for planning and what-if scenarios; get a real Loan Estimate before making decisions.
When the calculator asks for them. PITI calculations include property tax, insurance, and PMI; raw P&I calculations don't.
Lenders round payment amounts and may include escrow buffers. Property tax and insurance change over time. Real payments vary 1-5% from these estimates.

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