About the Loan Comparison Calculator
A loan with a lower monthly payment is not always the cheaper one. A longer term lowers the payment but adds a lot of interest. This calculator puts two loans next to each other. Enter the amount, the yearly interest rate and the term in years for each, and it shows the monthly payment, the total interest, the total cost and which loan costs less overall, with the difference. Type the amount, the yearly rate and the years for loans A and B and the loan comparison appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the Loan Comparison Calculator
- 1Enter the amount, the yearly rate and the years for loans A and B.
- 2Pick the units or options from the menus if the loan comparison tool offers them.
- 3Read the loan comparison in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the loan comparison
Home buyers use it to compare a 15 and a 30 year mortgage, or two lenders' offers. Car buyers compare dealer finance with a bank loan, and borrowers use it to decide whether a higher payment for a shorter term is worth it.
The best choice depends on cash flow as well as total cost. A lower payment gives breathing space, and money not spent on the payment can be invested. The tool shows the numbers so you can weigh them.
How the loan comparison is worked out
Monthly payment = amount × r ÷ (1 − (1 + r)^−n), with r the monthly rate (yearly rate ÷ 12) and n the number of months. Total interest = payment × n − amount. A 200,000 loan at 6 percent over 30 years costs 1,199.10 a month and 231,676 in interest. The same amount at 5.5 percent over 15 years costs 1,634.17 a month but only 94,150 in interest. Loan B costs 137,526 less overall, though its payment is 435 higher each month.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Two loans side by side
- Total interest and cost
- Shows which is cheaper
Mistakes to avoid with loan comparison
The calculator covers a simple fixed-rate loan with equal monthly payments. It does not include fees, insurance, taxes or a change of rate. Compare the annual percentage rate (APR) of each offer when fees differ, and remember that paying early reduces the interest.
On phone and computer
On a phone, type into the boxes one after another and read the loan comparison underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the loan comparison move. The loan comparison calculator works the same on both. Comparing offers is easier when you can look at each in detail. Use the Loan Calculator for one loan's payments, the Amortization Calculator for the full schedule, and the APR Calculator to see yearly cost with fees.
Features
- Shorter term, less interest
- Compare APR when fees differ
- Fixed rate only
- Clear messages when the loan comparison inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate loan comparison?
Monthly payment = amount × r ÷ (1 − (1 + r)^−n), with r the monthly rate (yearly rate ÷ 12) and n the number of months. Total interest = payment × n − amount. A 200,000 loan at 6 percent over 30 years costs 1,199.10 a month and 231,676 in interest. The same amount at 5.5 percent over 15 years costs 1,634.17 a month but only 94,150 in interest. Loan B costs 137,526 less overall, though its payment is 435 higher each month.
What is the formula for loan comparison?
Monthly payment = amount × r ÷ (1 − (1 + r)^−n), with r the monthly rate (yearly rate ÷ 12) and n the number of months. Total interest = payment × n − amount. The loan comparison calculator applies it exactly and rounds only the displayed answer to six significant figures.
Why does a longer loan cost more?
Interest is charged on the balance for more months, so the total paid in interest is bigger even with a lower rate.
Should I take the lower payment?
Only if you need the cash flow. Otherwise a shorter term saves a lot of interest.
Does the tool include fees?
No. Add fees to the amount to see their effect.
Is this loan comparison calculator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.