Free tool · Step 03

Debt payoff calculator
avalanche vs snowball

Add your debts below. See exactly when you'll be free — and how much interest each method saves you.

Avalanche method Snowball method Interest saved Payoff timeline
1
Your debts
2
Extra monthly payment
Extra on top of minimums
Even £50/month extra makes a significant difference
£
/ mo
Total debt
£0
across all debts
Min. payments
£0
combined monthly
Total payment
£0
minimums + extra
Avalanche
Saves most
months to debt-free
Total interest paid
Debt-free date
Highest interest rate debt first. Mathematically optimal — minimises total interest across all your debts.
Snowball
months to debt-free
Total interest paid
Debt-free date
Smallest balance first. Builds momentum through quick wins — often better for people who need motivation to stay on track.
Ardlight insight
Add your debts above to see your personalised insight.
Total balance over time
Avalanche
Snowball
Avalanche payoff order (highest rate first)

Common questions

Pay minimums on all debts, then direct any extra money at the highest interest rate debt first. Once it's cleared, roll that payment into the next highest rate. Mathematically, this minimises total interest paid across all your debts.
Pay minimums on everything, then attack the smallest balance first regardless of interest rate. The boost of eliminating a debt entirely can help you stay motivated — which matters more than the maths if you're likely to give up otherwise.
Avalanche almost always saves more. The difference depends on the gap between your interest rates and balances. Use the calculator above to see exactly how much you'd save with your specific debts.
If your interest rate is above 6%, pay off debt first. High-interest debt is a guaranteed negative return that no investment reliably beats. Always claim your employer pension match first — that's an instant 50–100% return. See our Step 3 guide for the full framework.