Clear numbers for money decisions.

Model debt payoff, home costs, savings, and retirement without creating an account. Change an input and see the estimate update immediately.

Calculations run on this device. Share links keep inputs after the #, outside normal server requests.

Choose by the decision you’re making

Each tool shows its assumptions, a worked example, and the formula behind the result.

Estimates you can inspect

PayoffCalcs is built by a developer, not a financial adviser. The site documents its formulas, cites outside data where it is used, and states where real-world fees or lender rules can change the result.

Recently published guides

Plain-language explanations that connect the calculators to common decisions.

Browse all guides