Visible method
The calculation model is explained rather than treated as a black box.
Calculate with context
Calculators
Calculations you can inspect, challenge, and reuse.
Compare scenarios with visible formulas, editable assumptions, and guidance for interpreting the result.
What you can expect
Understand the number before using it.
Every calculator states its method, assumptions, limitations, and the difference between a scenario and a forecast.
Editable assumptions
Defaults and ranges are easy to change and compare.
Useful interpretation
Result cards explain what the number does and does not mean.
Available now
Browse calculators.
3 tools are ready to use.
Credit Card Payoff Calculator
Compare fixed, minimum-payment, and target-date plans, then see payoff time, interest, payment milestones, and the effect of extra payments.
FreeLocal browser data
View details Open Calculator
Investment & Savings Calculator
Compare low, base, and high growth scenarios, account for inflation and costs, and estimate the contribution required for a goal.
FreeLocal browser data
View details Open Calculator
Loan Repayment Calculator
Model payments, total interest, extra principal, variable rates, balloon structures, lender offers, and refinance break-even.
FreeLocal browser data
View details Open Calculator
Before use
Every tool answers the operational questions.
- What information does the tool receive?
- Does anything leave the browser?
- Which assumptions shape the result?
- What is the pricing model?
- Where are the limitations and support routes?