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Debt Calculators

Debt Avalanche Calculator

Pay highest-APR debts first with an avalanche strategy. Project the optimal payoff order, timeline, and the total interest saved.

Simulates payments month by month: minimum on every debt plus the entire extra payment piled onto the highest-APR active balance.

Your debts

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Avalanche payoff
2 yr 3 mo
Pay off all 3 debts in 2 yr 3 mo with $2,312 total interest. Order: Credit card A → Credit card B → Auto loan.
Months to debt-free
2 yr 3 mo
Starting total balance
$14,500
Total interest
$2,312
Total paid
$16,812
Payoff order
#DebtStartingPaid offInterest
1Credit card A$800Month 3$26
2Credit card B$4,200Month 14$546
3Auto loan$9,500Month 27$1,739
Overview

How the Debt Avalanche Calculator Works

The debt avalanche is the mathematically optimal payoff strategy: attack the highest-APR balance first to kill the most expensive interest as fast as possible. This calculator runs the schedule month by month so you can see the order, the months to debt-free, and the exact dollar interest you'll save versus paying every minimum.

Formula

The Math Behind the Calculator

Each month: charge interest on every balance, pay each debt its minimum, then apply the entire remaining extra payment to the highest-APR active balance. When that debt hits zero, roll its minimum + extra onto the next-highest APR. Repeat until all balances are zero.

Example

A Worked Example

Same three debts — $800 at 22%, $4,200 at 18%, $9,500 at 12% — with $1,000/mo budget. Avalanche pays off in ~17 months but with closer to $1,700 in interest (about $200 less than snowball) because it kills the 22% APR card immediately, then the 18% card, before touching the 12% balance.

How to use

How to Use the Debt Avalanche Calculator

  1. 1List every debt: name, balance, APR, and minimum payment.
  2. 2Enter the extra payment you can add beyond minimums.
  3. 3Compare to snowball — if the interest difference is small, snowball's psychological wins may be worth it.
Interpretation

What the Results Mean

  • Payoff order is highest APR to lowest — the mathematically cheapest sequence.
  • Total interest is the minimum you can pay given your budget and these balances.
  • Months to debt-free shows when the last balance disappears.
Avoid

Common Mistakes to Avoid

  • Switching strategies mid-plan — the savings come from sticking with the order to the end.
  • Treating promotional intro APRs as the long-term rate; the post-intro rate is what avalanche should target.
  • Charging new purchases on the highest-APR card while paying it down.
Keep going

Related Calculators

Debt Snowball Calculator

Pay debts smallest-to-largest with a snowball strategy. Project the payoff order, timeline, and total interest for your full debt list.

Debt Payoff Calculator

See exactly how long it will take to pay off any debt — and what the interest will cost you along the way.

Debt Consolidation Calculator

Compare paying off multiple debts individually against rolling them into a single consolidation loan — monthly payment, total interest, and projected savings.

Credit Card Payoff Calculator

Calculate how long it will take to pay off your credit card — or the payment needed to clear it by a target date.

FAQ

Frequently Asked Questions

Is avalanche always cheaper than snowball?+

Yes, by definition — it pays down the most expensive interest first. The dollar gap is usually small for short payoff plans and grows with larger, longer debt loads.

What if two debts have the same APR?+

Order doesn't matter mathematically; pick whichever feels more motivating. Most people pick the smaller of the two.

Should I include 0% intro APRs?+

Use the post-intro APR for avalanche ordering — that's the rate you'll actually pay if the balance isn't gone by the end of the promo.

Financial Disclaimer

This calculator is for educational and estimation purposes only. It does not provide financial, mortgage, tax, investment, or legal advice. Actual rates, payments, taxes, fees, insurance costs, eligibility, and loan terms vary by lender, location, credit profile, and market conditions. Always compare official offers and consult a qualified professional before making financial decisions.

Last updated June 2026 · Prepared by the mCalculator Editorial Team