What interest costs you, and what it earns you.
Calculators for the money questions that come down to compound interest: clearing a balance, growing a deposit, and what a mortgage decision adds up to over its term. Every page shows its formula and names its source.
Free. No signup, no email, and nothing you type leaves your browser.
3 calculators
Debt
What a balance costs to carry, and how long it takes to clear.
- Credit card payoff How long a balance takes to clear, and the interest it costs.
- Debt snowball Several debts at once. Snowball and avalanche, side by side.
- Minimum payment What paying only the minimum costs, under both issuer formulas.
7 calculators
Mortgage
Recasting, releasing equity, and paying down early.
- Reverse mortgage What a HECM could release. No form, no lead capture.
- Mortgage recast A lump sum against the balance, keeping the same term.
- Mortgage insurance What PMI adds, and when it can come off.
- HELOC payoff The payment jump when the interest-only draw period ends.
- Biweekly payments What twenty six half payments a year actually saves.
- Bridge loan Carrying two properties, with the fees annualised.
- Adjustable rate The hard ceiling your caps put on the payment.
6 calculators
Savings
What a deposit grows to, and how long a pot lasts.
- CD calculator What a certificate of deposit pays by maturity.
- Savings withdrawal How long a pot lasts at a given monthly draw.
- APY and APR What a rate is worth once compounding is counted.
- Money market Growth on a variable rate, with the variability stated.
- Savings goal What to put aside monthly to reach an amount by a date.
- CD ladder Staggered maturities, compared honestly against one long term.
2 calculators
College
Saving for education costs that are years out.
- Pell Grant An estimate from the Student Aid Index on your FAFSA summary.
- 529 calculator What regular contributions grow to by the first tuition bill.
How this site works
Every calculator here shows the formula it used and cites the authority it follows, because a number you cannot check is a number you have to take on trust. Where a result depends on an assumption, the assumption is printed next to it rather than buried.
This site computes. It does not advise. You will not find a recommended option, a best choice, or a "you should" anywhere on it. What to do with a figure depends on things a calculator cannot see: what else you owe, what you have put by, and how steady your income is. The arithmetic is here so you can weigh that yourself.