4 tools
Loans & Debt
Every fixed-rate instalment loan follows the same arithmetic, whether it is a personal loan, a student loan or a consolidation. These tools expose that arithmetic, including what changes when you pay more than the minimum.
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Amortization Calculator
See where every payment goes — interest, principal and balance, payment by payment — and what actually changes when you pay more often or pay more.
This builds the full amortisation schedule for a fixed-rate loan: every payment, split into interest and principal, with the balance remaining after each one. It shows the payment, the total interest over the term, and what that interest costs per $100 borrowed. Because the payment frequency and an optional extra payment are both inputs, it also answers the question schedules are usually used to settle — whether paying more often, or paying more, is what actually saves money. The two effects are reported separately, because they are very different in size and are almost always conflated.
Open the amortization calculatorAlso in loans & debt
Each one answers a different question, not a rephrasing of the same one.
- Debt-to-Income Ratio Calculator Work out the two ratios lenders actually look at — housing alone, and every debt together — and see how much of your monthly obligations would need to clear to reach the conventional 36%.
- Credit Card Payoff Calculator Work out how long a card balance takes to clear and what the interest costs — and what changes if the payment stays the same every month instead of shrinking with the balance.
- Debt Payoff Calculator Price the snowball against the avalanche on your own debts — and find out whether the choice is worth anything at all, which is often less than the argument about it suggests.
Answered here
Questions these tools actually answer.
Each links to the tool that answers it, where the full explanation sits beside the calculation.
- Does paying biweekly really save thousands in interest? Amortization Calculator
- Then is there any point switching to a more frequent payment? Amortization Calculator
- What if my lender will not take fortnightly payments? Amortization Calculator
- Why is so much of my early payment interest? Amortization Calculator
- Why does my final payment differ from all the others? Amortization Calculator
- Should I pay extra on the loan or invest the money instead? Amortization Calculator