Use this for a total debt figure. Snowball pays smallest debts first for quick wins; avalanche pays highest-rate debts first to save the most interest. With one total figure, the maths below is the same — the method matters when you list debts separately, smallest first (snowball) or highest rate first (avalanche).
Total debt £5,000 at 18%, paying £200 a month: about 31.6 months to debt-free. Extra payments shorten this sharply — try £250 a month in the calculator and compare.
Results are estimates for information only, not financial advice. If debt is unmanageable, seek free debt advice in your country.