Find the interest rate of an installment purchase
Find the interest hidden in installment plans: enter the cash price, the number of installments and the amount of each.
What is the interest rate on the installments?
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Find the interest rate of an installment purchase: what it is for
Many stores advertise installments without saying the rate. Enter the cash price, the down payment, the number of installments and the amount of each: the calculator finds the monthly rate with the standard amortization formula and shows the total interest.
Check the first-payment-at-purchase option for 1 + n plans.
How to use
- Type the cash price and the down payment.
- Enter the number and amount of installments.
- See the monthly and yearly interest rate.
When to use it
- Decide between paying cash or in installments.
- Compare offers from different stores.
- Check the rate of a loan.
Frequently asked questions
How do I find the interest on an installment purchase?
Compare the cash price with the installments. The calculator finds the monthly rate that makes the installments worth exactly the cash price, using the standard amortization (Price) formula used by stores and loans.
Does a first payment at purchase change the rate?
Yes. When the first installment is paid at purchase (1 + n), you owe for less time, so the same installment means a higher rate. Check the option when that's the case.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.