Loan Comparison Calculator - Compare Loans Side by Side

Monthly payment, interest, and total cost for both offers
Measure	Loan A	Loan B
Monthly Payment	$489.15	$413.14 ✓
Total Interest	$4,349.22 ✓	$4,746.30
Total Cost	$29,349.22 ✓	$29,746.30

Total cost: Loan A vs. Loan B
Item	Value
Loan A	$29,349
Loan B	$29,746

Total interest: Loan A vs. Loan B
Item	Value
Loan A	$4,349
Loan B	$4,746

How to use this tool

Enter the loan amount, interest rate, and term for Loan A.
Enter the same details for Loan B.
Review and compare monthly payments, total interest, and total cost side by side.

How to compare loans

Enter two fixed-rate offers, including each principal, annual interest rate, and term in months. The calculator updates the monthly payment, total interest, and total of scheduled payments as you adjust an input. Looking at all three figures helps you separate the amount due each month from what the loan costs across its full term.

Monthly payment: the scheduled amount due each month and its cash-flow impact.
Total interest: the estimated interest across all scheduled payments.
Total cost: the sum of scheduled payments, including principal and interest.
Fees and penalties: check lender disclosures separately; they are not added here.

For a fully amortizing loan with a fixed monthly rate, the scheduled payment is calculated as M = P × r × (1 + r)ⁿ ÷ ((1 + r)ⁿ − 1), where P is principal, r is the entered annual interest rate divided by 12, and n is the number of monthly payments. At a zero rate, the principal is divided evenly by the term. Total interest is the unrounded payment multiplied by the number of months, minus principal; displayed values are rounded for readability.

The percentage field is applied directly as the loan's annual interest rate. The calculator does not solve for a fee-inclusive APR or add origination fees, points, mortgage insurance, taxes, or prepayment penalties. If an offer includes those costs, review its loan estimate and compare them separately; a lower scheduled payment alone does not establish that an offer is cheaper.

Total cost of borrowing example

Loan option	Amount	Rate	Term	Monthly payment	Total interest	Total of payments
Option A	$30,000	5.0%	60 mo	$566.14	$3,968	$33,968
Option B	$30,000	4.5%	72 mo	$476.22	$4,288	$34,288

At these assumptions, Option B's payment is about $89.92 lower each month, while it accrues about $319.68 more interest over the full term. The example rounds interest and total payments to the nearest dollar; the calculator keeps full precision for its calculations and formats the results for display. A buyer comparing lender offers can use this difference to weigh monthly budget needs against the amount paid over time.

This tool assumes both offers have fixed rates and regular monthly payments. It does not model variable-rate changes, balloon payments, extra principal, irregular schedules, or the full cost of a mortgage with taxes and insurance. For a comparison between an existing loan and a refinance offer that includes closing costs, use the Refinance Calculator.

Frequently asked questions

What factors should I compare when choosing a loan?

The three most important factors are: (1) monthly payment - what you can afford each month; (2) total interest paid - the true cost of borrowing; (3) total amount paid - the sum of all payments. A lower rate is not always cheaper if the term is much longer.

Does a longer loan term always mean more interest?

When principal and rate are the same, a longer fully amortizing term generally lowers the monthly payment but increases total interest because you are borrowing for more months.

What is the standard amortization formula used?

Monthly payment M = P × r × (1+r)^n / ((1+r)^n − 1), where P is principal, r is the entered annual interest rate divided by 12, and n is the number of months. At 0%, the payment is P ÷ n.

Does the comparison include lender fees or taxes?

No. The entered annual interest rate is applied directly to the payment formula. Origination fees, points, insurance, taxes, closing costs, and prepayment penalties are not added to the estimates, so confirm those details in the lender disclosures.