Debt Snowball Calculator
Simulate the snowball method: pay minimums on all, then throw the surplus at the smallest-balance debt first — build momentum.
Input Data
Results
At a glance:Snowball: pay each debt's minimum, then direct all leftover of a fixed total budget to the SMALLEST-balance debt first. Month by month: interest = balance x annual/12; pay minimums; apply surplus to smallest balance; repeat until zero; sum months, total paid, total interest. Clearing one rolls its minimum into the next-smallest target (keeping total constant) for momentum. May pay slightly more interest than avalanche but is easier to sustain. WARNING: Fixed rates, on-time, no new debt. Education, not advice.
Formula
Monthly interest_i = balance_i × rate_i / 12.
Budget = Σ min-payments (fixed each month).
Surplus → the smallest-balance debt; repeat until all balances are zero.
$$\\text{Interest}_i = \\text{Balance}_i \\times \\dfrac{\\text{Rate}_i}{12}$$$$\\text{Budget} = \\sum_i \\text{MinPayment}_i \\quad (\\text{Monthly fixed})$$How to Use
- Enter up to four debts' balances, rates and minimums.
- Enter a total monthly budget covering all minimums plus surplus.
- View months, total paid, total interest for the snowball method.
FAQ
How does the snowball method work?
You pay every debt's minimum, then send all extra from a fixed total budget to the debt with the smallest balance. Once cleared, you roll its old minimum into the next-smallest debt. The quick wins build motivation to keep going.
How does it differ from avalanche?
Snowball orders by balance (smallest first) for momentum; avalanche orders by interest rate (highest first) to save the most money. Snowball may cost a bit more interest but can be easier to stick with. Both require keeping the total monthly payment constant.
Does snowball usually cost much more interest?
Often not by much. With the three debts in this page's comparison, snowball pays only about HK$403 more interest and takes about 1 extra month versus avalanche. The gap depends on how balances and rates are distributed — if the smallest balance is also the highest rate, the two are nearly identical; if the smallest is low-rate, the gap is larger.
Is snowball suitable for Hong Kong's high-interest debt?
Hong Kong credit-card revolving APRs commonly run ~20%-36%; if you hold multiple cards and a personal loan, snowball clears small card balances fast and reduces the number of bills to manage. But if one high-rate card has a large balance, snowball may accrue more interest — consider switching to avalanche or tackling the most expensive one first.
What are the assumptions and data basis of this calculator?
It simulates month by month: each debt accrues interest (balance x annual rate / 12), minimums are paid first, and the fixed total budget's surplus goes to the smallest balance, repeating until all are cleared, tallying months, total paid and total interest. Snowball/avalanche are internationally recognised repayment concepts; for Hong Kong debt-management guidance see the Investor and Financial Education Council (IFEC). Results assume fixed rates and on-time monthly payments; for planning reference only.
Related Tools
References
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.