Debt Payoff Calculator
Compare snowball and avalanche payoff plans.
Details
on top of minimums
Debt-free in (avalanche)
3 yr 2 mo
Paying $785 per month
Total interest
$4,314
Total paid
$29,314
This works out how long your debts take to clear and what they cost in interest, at your current payment or a higher one.
It compares the avalanche and snowball orderings, so you can see what each approach costs and saves.
How to pay off debt faster
Paying off debt is a race between your payment and the interest. Anything above the interest reduces the balance; anything below it means the balance grows.
Minimum payments are set close to that line on purpose. On a $10,000 balance at 22%, the first month's interest is $183.33. A minimum payment of 2% of the balance is $200, so only $16.67 actually reduces what you owe.
That is why the size of the payment matters far more than the size of the debt. Paying $300 a month clears that balance in 52 months with $5,596 of interest. Paying $250 takes 73 months and $8,189, so $50 a month is worth $2,593 and 21 months.
Over 91% of the payment covers interest. This is the mechanism behind balances that seem never to move despite years of payments.
What to enter
- Balances and rates
- List every debt with its own rate. The rates are what decide the order to attack them in.
- Minimum payments
- You must keep paying the minimum on everything, or the accounts fall delinquent.
- Extra monthly amount
- Whatever you can add above the total minimums. This is the entire engine of any payoff plan.
- Strategy
- Avalanche targets the highest rate first. Snowball targets the smallest balance first.
Avalanche against snowball
- Avalanche
- Pay minimums everywhere, put everything spare on the highest rate. Mathematically optimal: always the least interest and usually the fastest.
- Snowball
- Pay minimums everywhere, put everything spare on the smallest balance. Costs more in interest, but clears individual debts sooner.
- Why snowball persists
- Research on consumer debt repayment has found people are more likely to stick with a plan that closes accounts early. A slightly worse plan you finish beats a better one you abandon.
- Consolidation
- Replacing several debts with one lower-rate loan. It helps only if the new rate is genuinely lower and you stop adding to the old accounts.
What this assumes
No new borrowing during the payoff. Adding to a balance while paying it down changes the answer entirely.
Rates are treated as fixed. Most credit card rates are variable and move with the prime rate.
How to calculate your debt payoff plan
Total your minimums, decide what extra you can add, then choose an order and hold it.
- balance × APR ÷ 12
- This month's interest, which the payment must clear first
- principal reduced
- What is left. If this is small, the payment is too close to the interest
List every debt with its rate. Balance, APR and minimum payment. Seeing them together is usually the most useful part of the exercise.
Find your extra amount. Total the minimums, then work out what else you can commit each month. Even $50 changes the timeline materially.
Pick an order and keep it. Avalanche for the lowest cost; snowball if early wins keep you going. Choosing either and sticking to it beats switching between them.
Roll each cleared payment into the next debt. When one debt clears, add its whole payment to the next. This is what makes the plan accelerate rather than stay flat.
See a worked example: what an extra $50 a month is worth
- Balance
- $10,000
- Rate
- 22% APR
At $250 a month: 73 months to clear, $8,189 of interest.
At $300 a month: 52 months to clear, $5,596 of interest.
An extra $50 a month saves $2,593 and 21 months.
At the $200 minimum it is a different story entirely: only $16.67 of the first payment reduces the balance, and at that rate the debt barely moves.
$50 a month saves $2,593 and 21 months
Frequently asked questions
Avalanche is mathematically better. Paying the highest rate first always costs the least interest, and it is usually also the fastest.
Snowball clears whole debts sooner, and research on how people actually repay consumer debt has found that closing accounts early makes them more likely to keep going. If you have abandoned payoff plans before, that is a real argument for it.
Because the minimum payment is set just above the interest. On $10,000 at 22%, the interest alone is $183.33 a month, and a $200 minimum leaves $16.67 of progress.
Minimums are usually a percentage of the balance, so they also fall as the balance does, which stretches the tail out even further. Paying a fixed amount instead of the minimum is the single most effective change.
Usually a small emergency fund first, of around $1,000, then attack the debt, then build the fund properly.
The reason is practical. Without any buffer, the next unexpected bill goes straight back onto the card, and the payoff plan collapses in a way that is very discouraging.
Only if the new rate is genuinely lower and you stop using the old accounts. Moving $20,000 from 22% cards to a 12% personal loan is a real saving.
It fails when the cards get used again. Then there is a consolidation loan and new card balances, which is worse than the starting point.
It can be, if you will genuinely clear the balance within the 0% period. Transfer fees are commonly 3-5%, so a $10,000 transfer costs $300-$500 upfront.
The risk is the end of the promotional period, when the rate can jump above where you started. Divide the balance by the number of promotional months and treat that as the required payment.
Compare the rate against what you can expect to earn. Clearing 22% debt is a guaranteed 22% return, which no investment can promise.
A 3% mortgage is the opposite case: keeping it while investing at an expected 7% usually makes sense. The dividing line sits roughly where the debt rate meets your realistic expected return.
Problems people actually run into
Paying the minimum and assuming progress is being made
Years of on-time payments with a barely-moving balance is not a failure of discipline. It is the minimum payment working exactly as designed, with over 91% of it going to interest.
Switch to a fixed monthly amount above the minimum. Because minimums shrink as the balance does, a fixed payment accelerates automatically.
Clearing the cards and keeping them open with no plan
A paid-off card is a paid-off card and an available credit line. Without a change in what caused the balance, it frequently returns.
Keeping the accounts open helps your credit utilisation, so closing them is not automatically right. The thing that has to change is the spending, and a budget is a more reliable defence than willpower.
Results are estimates for general information only and are not professional financial, medical, or legal advice. Read our full disclaimer.
Last updated: September 4, 2026