A Personal Loan Calculator helps you estimate how much you’ll repay each period, how much interest you’ll pay over the life of the loan, and how long it will take to become debt-free. With just a few inputs—loan amount, interest rate, term, and frequency—you can compare scenarios and make confident borrowing decisions.
How the Personal Loan Calculator works
Personal loans are typically amortizing loans with fixed interest rates and regular repayments. The calculator uses your annual percentage rate (APR), the loan term, and your chosen repayment frequency (monthly, fortnightly, or weekly) to compute a base repayment using the standard amortization formula. If you add extra repayments or ongoing fees, the tool models those effects to estimate your true cost and payoff timeline.
Inputs you can control
- Loan amount: The amount you borrow before fees.
- APR (interest rate): The yearly interest cost expressed as a percentage.
- Loan term and unit: Choose months or years to match your lender’s offer.
- Repayment frequency: Monthly (12 payments/year), fortnightly (26), or weekly (52).
- Upfront fee: A one-time charge. You can choose to pay it upfront or finance it into the loan.
- Ongoing fee per period: A fixed charge that is added to every repayment.
- Extra repayment per period: An additional amount you voluntarily pay to reduce interest and finish sooner.
What you’ll learn from the results
The calculator shows your estimated repayment per period, the number of payments until payoff, total interest cost, total fees, and the grand total paid. If you include extra repayments, you’ll typically see fewer payments and lower interest compared to the minimum scheduled amount. Ongoing fees are included in the total cost but do not reduce your principal balance.
Why extra repayments matter
Even modest extra repayments can significantly cut your total interest. Because interest accrues on your remaining balance, any extra you pay directly reduces the principal, which lowers interest in subsequent periods. Over time, this snowball effect shortens your loan and saves money.
Tips for accurate comparisons
- Match frequency to reality: If your salary is weekly or fortnightly, use the same frequency to smooth your cash flow.
- Include all fees: Add the ongoing fee per period and any upfront fee for a true apples-to-apples comparison.
- Test scenarios: Try different terms and extra repayment amounts to find your optimal balance between payment size and total cost.
- Check zero-interest edge cases: If your APR is 0%, the payment simply equals principal divided by the number of periods, and extra repayments accelerate payoff even more.
Understanding the math
For loans with interest, the periodic rate is the annual rate divided by payments per year. The base repayment is calculated using the amortization formula so that each payment covers that period’s interest plus a portion of the principal. As the principal declines, the interest portion of each payment falls and the principal portion rises. Added extra repayments increase the principal portion further, bringing down interest faster.
Limitations and assumptions
This Personal Loan Calculator assumes a fixed interest rate for the life of the loan and that ongoing fees are charged every repayment period. It does not account for late fees, rate changes, payment holidays, or early repayment penalties. Final payment amounts may be smaller than regular payments when the balance approaches zero.
Next steps
- Enter your loan details and fees.
- Experiment with extra repayments to see time and interest savings.
- Compare multiple term lengths to fit your budget.
- Use the results to negotiate a better rate or fee structure with lenders.
By modeling your options with the Personal Loan Calculator before you apply, you can pick a repayment plan that minimizes interest, fits your cash flow, and gets you debt-free sooner.