Debt Payoff Calculator
Compare avalanche and snowball strategies across all your debts and see which wins.
Inputs
Format: balance, APR%, minimum payment, [optional name]. Up to 5 debts.
Amount above all minimums available to accelerate payoff.
Avalanche — Payoff Time
45months
Avalanche — Total Interest
$3,637.95
Snowball — Payoff Time
46months
Snowball — Total Interest
$4,098.75
Interest Saved by Avalanche
$460.80
How much more the snowball strategy costs in interest.
Months Saved by Avalanche
1
Step by step
Debts entered
= 3 debts, $16,000.00 total
Monthly budget
Minimums ($310.00) + Extra ($200.00)
= $510.00
Avalanche result
= 45 months, $3,637.95 interest
Payoff order: Credit Card A → Credit Card B → Car Loan
Snowball result
= 46 months, $4,098.75 interest
Payoff order: Credit Card B → Credit Card A → Car Loan
Avalanche advantage
= Saves $460.80 and 1 month(s)
How it works
The avalanche strategy minimises total interest paid by targeting the highest-rate debt first. The snowball strategy maximises psychological wins by clearing the smallest balance first — you see debts disappear faster, which many people find motivating. Mathematically, avalanche always wins on total cost; the snowball's only edge is behavioural. This calculator runs month-by-month simulations for both so you can see the exact trade-off for your specific debts.
Formulas
Monthly interest per debt
Monthly interest = Balance × (APR / 12)
- B_j
- Balance of debt j
- APR_j
- Annual rate of debt j as decimal
Avalanche priority
Extra budget → debt with highest APR
Snowball priority
Extra budget → debt with smallest remaining balance
Frequently Asked Questions
Which strategy should I choose?
Avalanche minimises total interest — if your debts have very different APRs, the difference can be thousands of dollars. Snowball gives you quicker wins: paying off your smallest debt in a few months keeps you motivated. Research suggests people who use the snowball approach are more likely to stick with it and actually become debt-free.
How do I enter my debts?
One line per debt: balance, APR%, minimum monthly payment, and an optional name, separated by commas. For example: 4500, 23.99, 90, Chase Sapphire. You can enter up to 5 debts.
What does 'extra monthly budget' mean?
After paying the minimums on all debts, any money left over is your extra budget. This is the amount you can direct strategically — toward the highest-APR or smallest-balance debt depending on your strategy.
Why is the payoff time the same for both strategies?
If all your debts have the same APR, or if your balances happen to already be ordered from smallest to highest APR, both strategies produce the same result. The avalanche advantage grows with APR spread between debts.