401(k) Loan Calculator
Calculate 401(k) loan repayment, interest paid back to yourself, and the opportunity cost of lost market returns. See the true cost of borrowing from retirement.
Debt Calculator
Calculate total debt payoff time, interest costs, and savings with extra payments. Compare avalanche vs snowball strategies for multiple debts.
Your Debts
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%
$
$
%
$
$
%
$
$
Total Debt⧉
$48,000.00
3 accounts
Payoff Time⧉
81 months
6.8 years
Total Interest⧉
$9,089.00
Total paid: $57,089.00
Interest Saved⧉
$4,255.00
vs minimum payments only
Months Saved⧉
31 months
Min-only: 112 months
Weighted Avg Rate⧉
8.3%
Highest: 21.99%
Debt Breakdown
Credit Card
Car Loan
Student Loan
Payoff Timeline
| Month | Remaining Balance | Total Interest |
|---|---|---|
| 1 | $47,312.00 | $332.00 |
| 2 | $46,617.00 | $657.00 |
| 3 | $45,914.00 | $974.00 |
| 6 | $43,761.00 | $1,881.00 |
| 9 | $41,536.00 | $2,716.00 |
| 12 | $39,238.00 | $3,478.00 |
| 15 | $36,863.00 | $4,163.00 |
| 18 | $34,406.00 | $4,766.00 |
| 21 | $31,865.00 | $5,285.00 |
| 24 | $29,580.00 | $5,720.00 |
| 27 | $27,634.00 | $6,114.00 |
| 30 | $25,658.00 | $6,478.00 |
| 33 | $23,652.00 | $6,812.00 |
| 36 | $21,616.00 | $7,116.00 |
| 39 | $19,548.00 | $7,388.00 |
Planning notes, formulas, and examples
About the Debt Calculator
The Debt Calculator models a payoff plan for multiple debts such as credit cards, student loans, car loans, and personal loans.
You can compare the debt avalanche, which targets the highest rate first, with the debt snowball, which targets the smallest balance first. The calculator simulates payoff month by month and shows when you become debt-free, how much interest you pay, and how much extra payments change the result.
That makes it easier to turn a pile of balances and rates into a concrete repayment timeline.
When This Page Helps
Debt payoff gets easier to plan when the total interest cost and the effect of extra payments are visible in one place. Comparing avalanche and snowball methods also makes it easier to choose a strategy you can stick with consistently.
How to Use the Inputs
- Add each debt with its name, balance, interest rate, and minimum payment.
- Use presets for common debt scenarios or enter your own.
- Set extra monthly payment amount — even $50 makes a difference.
- Choose avalanche (highest rate first) or snowball (smallest balance first).
- Review payoff timeline, total interest, and savings vs minimum payments.
- Adjust extra payment to see accelerated payoff scenarios.
Formula used
Monthly Interest = Balance × (Annual Rate / 12). Avalanche: Extra payments target the highest-rate debt. Snowball: Extra payments target the smallest balance. Interest Saved = Min-Only Interest − Strategy Interest.Example Calculation
Result: Payoff: 52 months — Interest: $6,800 — Saved $3,200 vs min-only
With $200 extra per month using the avalanche method, all three debts are paid off in 52 months with $6,800 in total interest. Minimum payments only would take 72 months with $10,000 in interest — the extra payment saves $3,200 and 20 months.
Tips & Best Practices
- The avalanche method saves the most money mathematically — always attack the highest rate first.
- The snowball method can be more motivating — paying off small debts quickly creates momentum.
- Even $50 extra per month significantly reduces your payoff timeline and total interest.
- Once a debt is paid off, roll its payment into the next target — this is the "snowball" effect.
- Consider balance transfer offers (0% APR) for high-rate credit card debt while paying it down.
- Automate payments to ensure you never miss a minimum and consistently apply extra payments.
Avalanche And Snowball
The avalanche method minimizes total interest by attacking the highest-rate balance first. The snowball method focuses on the smallest balance first, which can provide faster visible progress. Both work mathematically; the difference is whether you value minimum interest or early momentum more.
Extra Payments Matter
Even modest extra payments shorten the payoff timeline because every dollar sent beyond the minimum reduces future interest accrual. The calculator shows how much that extra amount saves over time so the tradeoff is easy to see.
Planning A Real Payoff
The right plan is the one you can follow month after month. Showing the debt list, monthly allocation, and payoff schedule in one place makes it easier to keep the strategy practical rather than purely theoretical.
Sources & Methodology
Last updated:
Methodology
This page simulates multiple debts month by month using the balances, APRs, and minimum payments entered by the user. It compares minimum-only repayment with an accelerated payoff path where any extra monthly cash is applied according to the selected sequencing method, while interest continues to accrue on the remaining balances each month.
The result is a repayment-planning worksheet, not a creditor statement forecast. Actual accounts can change APRs, fees, or minimum-payment formulas over time, so the payoff date and interest totals should be interpreted as a constant-rate scenario rather than a contractual promise.
Sources
- Managing Debt (consumer.gov) — consumer.gov debt-management worksheet used as the general framework for building and prioritizing a repayment plan.
- How does my credit card company calculate the amount of interest I owe? (Consumer Financial Protection Bureau) — CFPB explanation of revolving-balance interest calculation underlying the month-by-month debt simulation.
Frequently Asked Questions
The avalanche directs all extra payments to the debt with the highest interest rate while making minimum payments on everything else. When the highest-rate debt is paid off, the freed payment rolls to the next highest rate. This minimizes total interest paid.
The snowball directs extra payments to the smallest balance first, regardless of rate. Paying off small debts quickly builds confidence and momentum. While it may cost slightly more in interest than the avalanche, the psychological benefits help many people stay committed.
Mathematically, the avalanche saves more money. Psychologically, the snowball may keep you motivated. The difference in total interest is often smaller than expected. The best strategy is the one you will actually follow through on.
Any extra amount helps. Even $25/month makes a meaningful difference over time. A common approach is to allocate any raises, bonuses, tax refunds, or savings from reduced expenses to debt payoff.
Build a small emergency fund ($1,000–$2,000) first, then focus on paying off high-rate debt (above 7-8%). Debt above 15% (credit cards) should almost always be paid first — no savings account earns that return risk-free.
Yes, especially for credit cards. Call your issuer, mention competing offers, and ask for a rate reduction. Balance transfer cards with 0% intro APR can also dramatically reduce interest while you pay down principal.
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