How to use this calculator
Compare installment loans using the amount borrowed, nominal annual interest rate, term in months and payment frequency. The result is a payment per selected period, together with the interest cost and remaining-balance schedule.
How the installment is calculated
The periodic interest rate is the annual rate divided by payments per year: 12 for monthly, 26 for biweekly or 52 for weekly. The term is converted from months to the corresponding payment count, rounding up if it ends between payment periods.
The installment equals P × r ÷ [1 − (1 + r)^−n]. For a zero-rate loan it equals principal divided by payment count. Each payment pays interest on the opening balance and uses the rest to reduce principal. The final payment cannot exceed the amount still owed.
Compare total cost, not only the installment
A longer term generally spreads repayment across more installments. Compare the total interest alongside the payment amount, and keep the interest-rate assumption unchanged when testing different terms.
These frequency options recalculate equal payments for the selected schedule. They do not simulate an accelerated plan that pays half a monthly installment every two weeks. Lender fees, daily interest, payment holidays and credit eligibility are excluded; use a lender’s actual schedule for a contractual comparison.
Example: a three-year loan
Borrowing $10,000 at 6% nominal annual interest for 36 months gives a monthly installment of approximately $304.22 before fees. A zero-interest $12,000 loan over 12 monthly payments instead requires exactly $1,000 each month.