Interest Comparison Calculator
Build multiple mortgage scenarios and compare interest rates, repayments, and total interest side by side
Add scenarios with different loan amounts, rates, or payment frequencies. The summary compares every scenario using a monthly equivalent so the results stay easy to scan.
| Scenario | Loan Amount | Rate | Payment | Monthly Equivalent | Total Interest | Total Repayment |
|---|---|---|---|---|---|---|
Scenario A | $500,000 | 4.30% | $2,474 monthly | $2,474 | $390,769 | $890,769 |
Scenario B | $500,000 | 4.80% | $2,623 monthly | $2,623 | $444,398 | $944,398 |
Comparison Snapshot
Monthly spread
$149
Lowest total interest
$390,769
Scenarios compared
2
How to use this comparison
Start with the same loan amount and term to compare pure rate differences. Then adjust amounts or payment frequency if you want to test a real lender structure.
- Use real rates from current lender offers where possible.
- Compare monthly equivalent as well as the regular payment amount.
- Check total interest before choosing an option based only on repayment size.
What this calculator does not include
The numbers are repayment estimates. Real mortgage decisions can also depend on lender fees, cashback, fixed-term conditions, break costs, and servicing policy.
- It does not model cashback or application fees.
- It does not compare lender policy or approval likelihood.
- It does not replace personalised mortgage advice.
Disclaimer: This calculator provides estimates only and should not be relied upon for financial decisions. Actual loan terms, rates, and eligibility may vary. Please contact a Mortgage Lab adviser for personalised advice.
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