Financing & Installment Calculator
"Buy now, pay later" and store financing hide the real price behind a small monthly number. Enter the amount, the interest rate (APR) and the term to see your true monthly payment and exactly how much the credit adds to the cost.
The monthly payment is not the price
Financing is designed to make expensive things feel affordable by shrinking the number you see. "Only $50 a month" sounds painless — but $50 a month for 24 months at a typical store-card rate can add well over a hundred dollars to a $1,200 purchase. This calculator uses the standard amortisation formula (the same maths lenders use) to show the real monthly payment and, more importantly, the total cost of credit: every extra dollar you pay for the privilege of paying later.
APR is the number that matters
The Annual Percentage Rate (APR) is the standardised, all-in cost of borrowing, which is why lenders are required to disclose it. A low monthly payment achieved by stretching the term over many months often hides a high total cost — you pay less each month but far more overall. Always compare the total you'll repay, not just the monthly figure.
"0% finance" has fine print. Genuine 0% deals can be sensible if you clear the balance in time. But many "deferred interest" offers retro-charge all the interest from day one if you miss the payoff date by even a little. Read exactly how the 0% ends.
How to use this tool
- Enter the amount financed, the APR (use 0 for an interest-free offer), and the term in months or years.
- Add any upfront fee to capture the true all-in cost.
- Read the total cost of credit — that's what financing actually costs you versus paying cash.
Before financing anything, it's worth asking whether waiting for a sale would beat the finance offer entirely — see our best time to buy guide and learn to avoid buyer's remorse.
FAQ
How is a monthly installment payment calculated?
Lenders use an amortisation formula based on the amount borrowed, the monthly interest rate (the APR divided by 12) and the number of payments. Each payment covers some interest and some principal. This calculator applies that exact formula, so the monthly figure it shows matches what a lender would quote, along with the total interest you'll pay over the full term.
What's the difference between APR and the monthly payment?
The monthly payment is what you hand over each month; the APR is the yearly all-in cost of borrowing. A low monthly payment can still come with a high APR and a high total cost if the term is long. Because the APR captures interest and certain fees in one standardised number, comparing APRs — and the total you'll repay — is far more revealing than comparing monthly payments.
Is 0% financing actually free?
It can be, but read the terms. A genuine 0% APR with no fees costs nothing extra if you make every payment on time. The catch is 'deferred interest' offers, which charge all the interest retroactively — back to the purchase date — if you don't clear the balance by the deadline. Always confirm whether it's true 0% or deferred interest, and whether any setup fee applies.
Should I finance a purchase or wait and pay cash?
If financing carries interest or fees, paying cash is cheaper — and saving up avoids the risk of debt on something you may regret. Financing can make sense for genuine 0% offers you'll pay off in time, or when spreading the cost is necessary. A useful test: if you couldn't afford to buy it outright fairly soon, that's a sign to wait rather than borrow.