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Debt Repayment Calculator

Estimate how long until your debt is cleared and how much interest you'll pay at your current monthly payment.

Short answer

Months to clear = -log(1 − (balance × monthly rate) ÷ payment) ÷ log(1 + monthly rate). Paying just the minimum on a credit card can take 20+ years. Adding even £50/month can cut years off and save thousands in interest.
Step 1 of 10%

Your debt

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How it works

Each month, interest is charged on the remaining balance, then your payment reduces what's left. The higher your payment relative to the interest, the faster the balance falls. We solve the standard amortisation formula for time.

Worked example

£3,000 credit card balance at 22% APR, paying £100/month: 41 months to clear, £1,100 interest. At £150/month: 24 months, £590 interest — saves £510 and 17 months.

Who should use this

  • Anyone with credit card or overdraft debt
  • People comparing snowball vs avalanche payoff strategies
  • Households planning a fixed monthly repayment

Common mistakes

  • ×Paying only the minimum (designed to maximise lender interest)
  • ×Not transferring to a 0% balance transfer card if eligible
  • ×Adding new spending to a card you're trying to pay off
  • ×Ignoring free debt advice from StepChange, Citizens Advice or National Debtline

Frequently asked questions

Snowball or avalanche method?

Avalanche (highest rate first) saves the most money. Snowball (smallest balance first) gives quick wins for motivation. Both work — pick what you'll stick to.

Should I use savings to clear debt?

Usually yes if debt rate exceeds savings rate. Keep a £1,000 emergency fund first to avoid going back into debt.

Will paying off debt hurt my credit score?

No — clearing balances improves your credit utilisation ratio and score. Don't close old cards immediately though.

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