Extra Payment Calculator — How Extra Payments Accelerate Debt Payoff

The minimum payment on a credit card is designed to keep you in debt as long as possible. It covers mostly interest and barely touches the principal. An extra payment — even a small one — changes the math dramatically.

See the Difference Yourself

1. Open the Debt Payoff Calculator.
2. Enter your debts.
3. Set extra payment to $0. Note the payoff date and total interest.
4. Now set extra payment to $100, $200, or whatever you can afford.
5. Compare. The difference is usually enormous.

Extra Payment Impact: Real Numbers

$15,000 credit card debt at 20% APR, $300 minimum payment:

Extra Monthly	Time to Payoff	Total Interest	Interest Saved vs Minimums
$0 (minimums only)	9 years, 6 months	$18,600	—
$50 extra	5 years, 4 months	$8,900	$9,700 saved
$100 extra	4 years	$6,200	$12,400 saved
$200 extra	2 years, 10 months	$3,700	$14,900 saved
$300 extra	2 years, 2 months	$2,500	$16,100 saved
$500 extra	1 year, 6 months	$1,500	$17,100 saved

Look at the jump from $0 to $50 extra. Just fifty dollars per month saves $9,700 in interest and cuts 4 years off the payoff. The first extra dollar you pay has the biggest relative impact.

Where to Find Extra Payment Money

The quick wins (today)

• Cancel unused subscriptions ($30-150/month for most people)
• Sell items you no longer use ($200-1,000 one-time)
• Downgrade a streaming plan or phone plan ($20-50/month)
• Cook one more meal at home per week ($40-80/month)

The bigger moves (this month)

• Pick up overtime or a side gig ($200-1,000/month)
• Negotiate a bill (insurance, internet, phone — $20-100/month)
• Apply a tax refund, bonus, or windfall entirely to debt
• Refinance a loan at a lower rate and redirect the savings

The Compounding Effect of Extra Payments

Extra payments have a compounding effect on debt payoff because every dollar you pay toward principal reduces the base on which interest is calculated. A $200 extra payment this month reduces next month's interest charge, which means more of next month's payment goes to principal, which further reduces the following month's interest, and so on.

This is compound interest working in your favor instead of against you. Every extra dollar accelerates the process more than the last.

The Lump Sum Strategy

Get a tax refund? Bonus? Birthday money? Gift? Side income windfall? Put it directly toward your highest-interest debt. A single $1,000 lump sum on a 20% APR credit card saves you $200+ in interest over the next year alone.

This feels less satisfying than spending the windfall on something fun. But the math is clear: every dollar applied to high-interest debt earns a guaranteed return equal to that interest rate. No investment offers a guaranteed 20% return.