InstalmentLoans

Loan Comparison Calculator

A loan comparison calculator runs the same repayment maths on two offers and compares them side by side. It shows the monthly repayment, the total cost and the estimated APR of each, so you can see which one costs less.

By the InstalmentLoans Editorial Team · Last updated 2 October 2026

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Enter your numbers and press Calculate. Nothing you type leaves your browser.

How this calculator works

Two loans can have the same amount but very different costs. This calculator runs the repayment formula on both and compares the results.

For each loan: M = P * r * (1 + r)^n / ((1 + r)^n - 1), and the total amount repayable includes any arrangement fee.

The cheaper loan is the one with the lower total cost, which is not always the one with the lower repayment. A longer term can lower the repayment while raising the total interest. An arrangement fee is included when estimating each APR.

Enter the rates and fees from your own offers. Rates vary by lender and credit profile.

Frequently asked questions

Why compare total cost and not just the repayment?
A lower repayment can come from a longer term, which adds months of interest and often a fee. The total amount repayable captures the full cost of each offer.
Should I compare loans with different terms?
Yes, but compare both the monthly repayment and the total cost. A longer term usually lowers the repayment and raises the total cost.
Does this comparison include fees?
It includes the arrangement fee you enter for each offer. The estimated APR also reflects that fee, which makes the two offers easier to compare.
What does it mean if the two offers tie?
A tie means both offers have the same rounded total cost. Look at the monthly repayment, the fee and any early repayment terms to break the tie.

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