Personal Loan Total Cost Calculator
This personal loan total cost calculator works out the monthly payment, total interest and full cost including upfront fees, so you can compare offers.
What it does
The Personal Loan Total Cost Calculator shows the real price of borrowing. It turns a loan amount, interest rate, term and any upfront fees into a monthly payment and the full amount you will repay over the life of the loan.
Data sources & parameters
This calculator uses standard financial formulas and runs entirely in your browser. It needs no external rate data — your result is computed only from the values you enter above.
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
payment = P × i ÷ (1 − (1 + i)^(−n)), where i is the monthly rate and n the number of months; total cost = payment × n + fees
How it works
The tool treats the loan as a standard amortised loan: each monthly payment covers interest on the outstanding balance plus a slice of the principal. It multiplies the payment by the number of months and adds fees to reveal the total cost and the interest you pay.
Where it is used
- Comparing two loan offers with different rates or terms
- Seeing how much a longer term adds to total interest
- Checking the true cost once upfront fees are included
Worked example
Borrowing $15,000.00 at 9% over 5 years with $200.00 in fees means a monthly payment of …. Across the term the loan costs …, of which … is interest.
What the personal loan total cost calculator does
The personal loan total cost calculator takes a loan amount, an interest rate, a term and any upfront fees, and works out a fixed monthly payment and the full amount you will repay over the life of the loan. You see what leaves your account each month, how much interest you pay, and the total cost from signing to the final payment.
Borrowing decisions are often made on the monthly payment because that is the number that fits a budget, but it hides the total. A loan with a low payment can cost thousands more than one with a slightly higher payment, because it runs for longer.
How the cost of a loan is built
A personal loan is usually amortised: each monthly payment covers interest on the balance you still owe and repays some of the principal. Early on most of the payment is interest, because the balance is large. As the balance falls, more of each payment goes to principal until the final payment clears the debt.
The monthly payment is fixed at the start so that, paid every month for the full term, it repays the loan plus all the interest:
payment = P × i ÷ (1 − (1 + i)^(−n))
P is the amount borrowed, i is the monthly interest rate (the annual rate divided by twelve) and n is the number of monthly payments. The payment multiplied by the number of months is the total repaid in instalments; adding upfront fees gives the total cost of the loan. The instalment total minus the amount borrowed is the total interest.
The four inputs
- Borrowing more raises both the monthly payment and the total interest in direct proportion, so borrowing only what you need is the simplest way to cut the cost.
- A higher interest rate increases every payment and the total interest sharply. A difference of one or two percentage points can add up to a meaningful sum over several years.
- A longer term spreads the debt over more months, lowering the monthly payment but increasing the total interest. A shorter term does the opposite.
- Upfront fees are added straight to the total cost and can turn a seemingly cheap loan into an expensive one.
How to use the calculator
- Enter the amount you want to borrow.
- Enter the annual interest rate the lender is offering.
- Enter the term in years.
- Enter any upfront fees, such as an arrangement or origination charge.
The monthly payment tells you whether the loan fits your budget. The total cost tells you what the loan costs. The total interest is the part of that cost you pay for borrowing, on top of the money you received.
Comparing offers
Lenders compete on the monthly payment and the headline rate. A fair comparison uses the total cost, which combines the rate, the term and the fees. Run each offer through the calculator and line up the totals: a loan with a lower monthly payment may cost more overall because it runs for longer, and a loan advertising the same rate as another may be more expensive once its fees are counted.
Term length
Stretching a loan from three years to five lowers the monthly payment, but because you owe the balance for two extra years, you pay far more interest.
A longer term can be sensible if the lower payment keeps your budget safe and stops you missing instalments. A shorter term saves interest if you can comfortably afford the higher payment. The calculator shows both sides of the trade.
Using the results
The output describes a fixed-rate, fully amortised loan. Real loans can carry variable rates, early repayment charges, or insurance sold alongside them, none of which appear here, so read your loan agreement for those details.
Borrow only what you need, prefer the shortest term you can comfortably afford, and always include fees in the comparison. Where a loan allows penalty-free overpayments, paying a little extra each month shortens the term and cuts the total interest. Check the offers in front of you before you sign anything.
This article is general information only and is not financial advice.
About This Personal Loan Total Cost Calculator
Use this personal loan total cost calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Frequently asked questions
How does the personal loan total cost calculator work?
What is the difference between the interest rate and the total cost?
Does a longer term make a loan cheaper?
Should I include fees in the comparison?
Is my data kept private?
About the author
