Debt

Debt Payoff Calculator

The mathematically cheapest repayment plan is only useful if you can stick to it. This calculator shows both the interest-efficient avalanche route and the momentum-focused snowball route.

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Your debts

Add each balance, APR and minimum payment.

Debts
Include unsecured debts you want to model together.

Repayment plan

Choose how much you can pay and which strategy you want to follow.

£/month
Must be at least enough to cover the minimum payments entered.
Avalanche prioritises highest APR; snowball prioritises smallest balance.

Your estimate

Use the result as a planning guide and change inputs to test the assumptions that matter most.

How this calculator works

Minimum payments are allocated to every debt first. Remaining monthly budget is directed to the priority debt: the smallest balance for snowball or highest APR for avalanche. When one debt clears, its payment capacity rolls to the next.

How to use it

  1. Add every unsecured debt you want to model.
  2. Enter balance, APR and minimum payment for each.
  3. Enter the total amount you can reliably pay toward these debts each month.
  4. Choose snowball or avalanche.
  5. Compare payoff time, interest and the order debts clear.

Assumptions and limitations

This is a planning model and does not account for changing rates, promotional periods, fees or lender-specific minimum-payment formulas. If priority bills or essential payments are at risk, repayment optimisation may not be the right first step.

Understand the decision

Helpful guides for this calculator

Use the calculator for the numbers, then use these guides for the practical choices, trade-offs and next steps behind the result.

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