Loan Comparison Calculator
Put two to four loan offers side by side and see which one really costs least once interest and every fee are counted.
Fill in the payment you make now if you know it; otherwise it is worked out from the time left. For a fair test, each offer's amount should match the balance you are moving.
Cost over time: chart and table
Interest and fees paid so far, year by year. Where two lines cross, the other offer becomes cheaper.
How your loans are compared
Cost of a loan = interest + every fee. The lowest cost wins, not the lowest payment.
- 1
Monthly payment
Offer B: $493Offer A: $420for 48 vs 60 months
- 2
Total interest
B: $3,662A: $5,202payments − loan
- 3
Add every fee
B: $3,662 + $0A: $5,202 + $0= $3,662 vs $5,202
- 4
Cheapest overall
Offer B winssaves $1,540vs Offer Atrue rate 8.50%
Read more: the formula, a worked example, fees, flat rates and refinancing
A loan with a lower monthly payment is not always the cheaper loan. A longer term, a higher rate or a big fee can make it cost far more in the end. This calculator works out each offer the same way and ranks them by their total cost: all the interest plus every fee.
The formula
monthly payment = loan × monthly rate ÷ (1 − (1 + monthly rate)^−months)
monthly rate = yearly rate ÷ 12 ÷ 100
total interest = monthly payment × months − loan
total cost = total interest + upfront fee + monthly fee × months
difference = this offer's total cost − the cheapest offer's total cost
Worked example
Offer A is $20,000 at 9.5% a year for 5 years. The monthly rate is 9.5 ÷ 12 ÷ 100 = 0.0079167, and (1.0079167)60 = 1.6050, so the payment is $20,000 × 0.0079167 × 1.6050 ÷ 0.6050 = $420.04. Sixty payments add up to $25,202.23, so the interest is $5,202.23.
Offer B is $20,000 at 8.5% for 4 years. The monthly rate is 0.0070833, (1.0070833)48 = 1.4033, and the payment is $20,000 × 0.0070833 × 1.4033 ÷ 0.4033 = $492.97. Forty-eight payments add up to $23,662.37, so the interest is $3,662.37.
Neither has fees, so Offer B is cheapest overall. It costs $72.93 more a month, but saves $5,202.23 − $3,662.37 = $1,539.86 in total and is paid off a year sooner.
Fees and the true yearly rate (APR)
An upfront fee means you get less money but repay the same amount. Offer C in Advanced mode is $20,000 at 7.9% for 5 years with a 4% fee ($800). The rate looks lowest, but the true yearly rate counting the fee is about 9.6%. The true rate is the interest rate at which the money you receive equals the value of all the payments you make, fees included.
- Paid up front: you pay the fee on day one (or it is taken out of the money you get).
- Added to the loan: the fee is borrowed too, so you pay interest on it.
- Monthly fee: an account or service charge with every payment. It counts in the total cost and the APR.
The true rate here is the monthly rate × 12, the way the US and India quote APR. The UK and EU quote APR compounded over the year, which reads a little higher: a monthly rate of 0.8% is 9.6% one way and 10.03% the other.
Flat rate vs reducing balance
A flat rate charges interest on the full loan for the whole term, even as you repay it. $10,000 at 10% flat for 3 years is $3,000 of interest, a payment of $361.11, and the same as about 17.9% on a reducing balance. Choose "Flat rate" for an offer quoted that way and compare the true yearly rates.
Balloons and extra payments
A balloon leaves a lump sum to pay at the end, which lowers the monthly payment but raises the interest, because more of the loan stays unpaid for longer. Extra monthly payments do the opposite: on a reducing-balance loan they cut the interest and end the loan sooner. Check that the lender allows overpayments without a charge.
Refinance check
Turn on the refinance check in Advanced mode to compare your current loan with each offer. The break-even month is the first month in which the new loan's interest and fees so far (plus any rise in what you owe, if the fee was added to the loan) are no more than the interest you would have paid on your current loan. If you expect to keep the loan beyond that month, switching pays off.
Example: a $150,000 balance at 7% with 20 years left costs $1,162.95 a month. A new 20-year loan at 5.5% with a $3,000 fee costs $1,031.83 a month. It breaks even in month 17 and saves about $28,468 over the life of the loan.
Assumes fixed rates and monthly payments for the whole term, interest worked out monthly, and a flat-rate loan's interest spread evenly over its months. Lenders' figures can differ slightly because of rounding, payment dates or how they share out flat-rate interest. Early repayment or exit fees on your current loan are not included; add them to the new offer's upfront fee. Checked on 10 October 2026.
Common questions
How do I compare two loan offers?
Compare the total cost, not just the monthly payment: all the interest plus any upfront and monthly fees. In the example, $20,000 at 9.5% for 5 years costs $420.04 a month, while 8.5% for 4 years costs $492.97 a month but saves $1,539.86 in total and is paid off a year sooner.
Why is the APR higher than the interest rate?
Because of fees. An upfront fee means you get less money but repay the same amount, so the true yearly rate is higher than the quoted one. A $20,000 loan at 7.9% for 5 years with a 4% fee looks cheapest on rate alone, but counting the fee its true rate is about 9.6%.
Is a lower monthly payment always better?
No. A longer term or a balloon lowers the monthly payment but usually raises the total interest, because more of the loan stays unpaid for longer. Look at each offer's total cost and true yearly rate (APR), then pick the cheapest one whose payment you can comfortably afford.
When is refinancing a loan worth it?
When you will keep the new loan past its break-even month, the first month in which its interest and fees so far are no more than the interest you would have paid on your current loan. Moving $150,000 at 7% with 20 years left to 5.5% with a $3,000 fee breaks even in month 17. Add any exit fees on your current loan.
Why do UK and US APRs look different?
The US and India quote APR as the monthly rate × 12. The UK and EU quote APR compounded over the year, which reads a little higher: a monthly rate of 0.8% is 9.6% one way and 10.03% the other. This calculator shows the true rate as the monthly rate × 12.
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