Tools

The Debt Payoff "What If" Calculator

Add every loan you have, then see what happens to your debt-free date and the interest you pay if you send in more than the minimum.

How to use this tool

Takes about two minutes. Nothing you type leaves your device, and nothing is saved.

  1. 1Enter your loans. For each one, type what you owe today, its yearly interest rate (APR), and the minimum payment on your statement. Add as many loans as you have.
  2. 2Pick an extra amount. This is how much more than the minimums you could pay each month, in total. Try a few different amounts, the results update instantly.
  3. 3Read the comparison. The tool shows paying only the minimums next to your plan, then walks through the math behind every number so you can check it yourself.
The loans pre-filled below are made-up examples so you can see how it works. Replace them with your own numbers.
1

Your loans

One card per loan. Credit cards, car loans, student loans, personal loans all work the same way here.

These are example loans, not yours.
Where to find these numbers: your latest statement or online account shows the balance, the APR (sometimes called "interest rate"), and the minimum payment (sometimes "amount due").
2

Your "what if"

What if you paid more than the minimums?

$
Where should the extra money go first? Your extra only goes to one loan at a time, the others still get their minimum. This picks which one gets it.
Roll paid-off payments into the next loan
When a loan hits $0, keep paying that same monthly amount toward the next loan instead of pocketing it.
3

The comparison

Same loans, two ways to pay them.

Minimums only
Pay exactly the minimum on each loan, nothing more. When a loan is paid off, that payment stops.
Debt-free in
Total interest paid
The extra you pay the lender for borrowing.
Total you pay back
Your plan
Debt-free in
Total interest paid
The extra you pay the lender for borrowing.
Total you pay back
Interest you'd save
Time you'd save

See it

Three pictures of the same result.

1. How fast your total debt shrinks

Each line shows everything you owe, month by month. The sooner a line hits $0, the sooner you're free. Hover or tap the chart to read exact values.

Minimums only Your plan
2. When each loan gets paid off

A shorter bar means that loan is paid off sooner. The time on the right is how long until that loan hits $0.

Minimums only Your plan
3. Where your money goes

Every dollar you pay does one of two jobs: shrink what you owe (blue) or pay the lender's interest (red). Less red is better.

Pays off your loans (principal) Interest (the cost of borrowing)

Loan by loan

Try different extra amounts

Same loans and same settings as above, only the extra amount changes. Your current choice is highlighted. Part of each saving comes from rolling paid-off payments forward, so turn that off in step 2 to see the extra amount's effect alone.

Extra per monthDebt-free inTotal interestInterest saved

"Interest saved" is compared with paying minimums only.

How we got these numbers

No black box. Here is every step, using the loans you entered.

1

Every month, each loan charges interest first. Your APR is a yearly rate, so we split it into 12 monthly pieces and apply it to what you currently owe.

monthly interest = balance × (APR ÷ 100) ÷ 12

2

Then you make your payments. Every loan gets at least its minimum. Part of each payment covers that month's interest, and whatever is left over reduces the balance.

new balance = old balance + interest − payment

3

The extra goes to one loan.

4

Repeat until every balance is $0. We run this month by month. Total interest is simply every month's interest added together, and the number of months is how long you're in debt.

Month 1, line by line

This is the first month of your plan, so you can verify the arithmetic by hand.

LoanStarting balance+ Interest− Minimum− Extra= New balance

Full month-by-month schedule (your plan)

Watch the "Interest" column shrink as the balance falls. That is the payoff of paying extra.

MonthInterest chargedYou paidWent to balanceTotal still owed

What these numbers assume, and what they mean

  • Fixed interest rates. Each APR stays the same until the loan is gone. Variable-rate loans and credit-card promo rates that expire will behave differently.
  • Fixed payments. We use your minimum as a flat monthly amount. Real credit-card minimums often shrink as the balance shrinks, which would make "minimums only" take longer than shown here.
  • No new borrowing. The model assumes you do not add to these balances, and there are no late fees, annual fees, or penalties.
  • Payments start next month and are made on time, every month, for the whole schedule.
  • Interest is calculated monthly as APR ÷ 12. Some lenders use daily interest, so your real figures can differ by a small amount.
  • Not tax or financial advice. This is a way to explore trade-offs. Your lender's own payoff quote is the final word.

Balance / principal: the amount you still owe, not counting future interest.

APR (annual percentage rate): the yearly price of borrowing, as a percent. A 20% APR on $1,000 costs about $200 over a year if you never pay it down.

Minimum payment: the smallest amount the lender requires each month to stay in good standing.

Interest: money you pay the lender on top of what you borrowed. It's the cost of the loan, and it's the number this tool is trying to shrink.

Debt-free date: the month your last loan reaches $0, assuming your first payment is next month.

Interest saved: total interest on minimums only, minus total interest on your plan.

Avalanche: put extra money on the loan with the highest APR first. Mathematically the cheapest order.

Snowball: put extra money on the smallest balance first. Often costs slightly more interest, but you cross finish lines sooner.

Rolling payments forward: when one loan is paid off, its old monthly payment goes to the next loan. This is why paying off debts speeds up over time.

  • Keep a small emergency cushion so a surprise bill doesn't land on a credit card.
  • Check whether any loan has a prepayment penalty. It's uncommon, but worth a call.
  • Ask your lender to apply extra payments to principal and not to future payments.
  • If you get an employer 401(k) match, compare it to your debt's APR before redirecting that money.
  • Paying off high-APR debt, like credit cards, is a guaranteed return equal to that APR.
@learntolovemoney

For educational purposes only. Not financial, tax, or legal advice. Results are estimates based only on the numbers you enter and the simplifying assumptions listed above. Your lender's actual payoff amounts, fees, and interest calculations may differ. Example loans shown are fictional.