Debt payoff calculator

Calculate a payoff plan that matches your actual balances and monthly budget.

Use the free Runway calculator below to compare debt avalanche and debt snowball strategies, estimate your debt-free date, and test how extra monthly payments change your payoff timeline.

Balance, APR, and minimum payment inputs
Projected debt-free date and total interest
Monthly what-if and target-date modeling

Interactive calculator

Enter your debts

Monthly debt budget Strategy What-if extra payment Target payoff month

Projection summary

See the payoff outcome

Strategy comparison

What if you add extra each month?

What monthly payment hits your target?

First six months

Month-by-month preview

Estimated payoff order

Which debt falls first?

The four inputs that matter most

The most useful calculator starts with your balances, APRs, minimums, and the total monthly amount you can direct toward debt. Those inputs determine the payoff order, the total interest cost, and whether a target debt-free date is realistic.

Method note: this public calculator is powered by the same payoff engine Runway uses inside the authenticated planner, so the free model and the signed-in workspace stay aligned.

What the result should explain

Output	Why it matters
Projected debt-free date	Lets you judge whether the plan is realistic for your current cash flow.
Total interest paid	Shows the hidden cost difference between strategies.
Monthly payment order	Turns an abstract payoff idea into a concrete routine.
Extra-payment scenarios	Helps you decide whether a refund, bonus, or monthly boost is worth allocating to debt.