Calculators
Practical calculators for mortgages, car and life insurance, personal injury, credit cards, retirement and loans — every result computed in your browser.
11 tools
Every calculator in this category is the same machine wearing different inputs: a balance that changes over time under a fixed rule, projected forward into a schedule you can inspect month by month. A mortgage, a credit-card balance, a student loan, a retirement pot and an insurance premium differ in what drives the rate and in what ends the arrangement — not in the arithmetic that connects them.
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Extra Payment Mortgage Calculator
See how extra monthly or one-off payments shorten a mortgage and how much interest they remove, with a month-by-month schedule. Runs locally.
Car Insurance Comparison Calculator
Compare car insurance quotes side by side: annual premium, deductible, and the out-of-pocket cost before cover starts. See the real yearly cost.
Personal Injury Settlement Calculator
Estimate what a personal injury claim may be worth from medical costs, lost earnings and pain and suffering, with liability and policy limits applied.
Life Insurance Needs Calculator
Work out how much life insurance your household actually needs to replace income and clear debts, and see the gap with the cover you already hold.
Credit Card Payoff Calculator
See how long it takes to clear your card balances and what the interest costs. Compare the avalanche and snowball methods with your own rates.
Retirement Savings Calculator
See what your savings become by retirement, the monthly income they support, how that compares with the 4% rule, and what Social Security covers.
Student Loan Repayment Calculator
Compare every federal repayment plan side by side: monthly payment, total interest, how long it runs, what gets forgiven and the tax bill that comes with it.
Home Equity Loan Calculator
Work out how much you could borrow against your home: your equity, the loan-to-value ceiling and the monthly payment on a HELOC or home equity loan.
Rent vs Buy Calculator
Compare renting with buying the same home over the same period — mortgage, taxes, maintenance, opportunity cost — and find your break-even year.
Debt Consolidation Calculator
See whether folding card balances into one loan saves money: compare the blended card rate with the loan rate, and weigh term against interest.
ROI Calculator
The return on an investment in three ways: total return, the annualized rate solved from your exact cash flows, and a benchmark comparison.
About Calculators
The reason to read the schedule rather than the headline number is that a single summary figure hides the shape of the deal. Two loans with identical rates and identical total cost can behave very differently if one front-loads interest while the other charges a fee at origination. Two retirement plans with identical contributions can end decades apart depending on whether money is added monthly or annually, and on whether returns compound at the same frequency as contributions.
None of these tools asks for an account, an email address or a credit check. You type balances and rates, the model runs locally, and nothing is transmitted. Treat the output as a projection built on the assumptions printed beside it, and treat those assumptions as the part worth arguing with — the arithmetic itself is just amortisation.
Frequently asked questions
How is interest calculated — daily, monthly or continuously?
The default is a nominal annual rate applied monthly, which is how most consumer loans are quoted and amortised: the annual rate divided by twelve, then applied to the outstanding balance each month. That is not the same as continuous compounding and not the same as an effective annual rate. Where a lender quotes an APR, the APR folds fees into a nominal annual figure and is the better number for comparing products; where it quotes a monthly rate directly, use the monthly figure.
Why do different calculators give different answers for the same loan?
Almost always because they disagree about an assumption rather than about arithmetic. The three usual suspects are whether payments fall at the beginning or the end of the month, whether fees are financed into the balance or paid at closing, and whether the quoted rate is nominal or effective. A payment-timing difference shifts the result by roughly one month of interest per year of term; financed fees shift it by the fee's future value. Each page here states the convention it uses so two tools can be compared on equal terms.
Are these results financial advice?
No. These are arithmetic projections of the numbers you enter. They do not know your tax position, your risk tolerance, your other debts, your local regulations or the terms of the specific product you have been offered. Use them to understand the shape of a decision — what happens to the payoff date when you add a hundred dollars a month, how much of a thirty-year loan's total cost is interest — and take the actual decision to a licensed adviser or to the full terms of the offer.
What assumptions do you make about inflation and taxes?
Unless a calculator states otherwise, the figures are nominal: the projected amounts are what an account would literally contain, not what they would buy. No tax is modelled on growth, on interest earned or on withdrawals, and no inflation adjustment is applied. That keeps outputs comparable with each other and with the statements your bank sends you, but it also means a retirement income figure is not the same as purchasing power decades from now, and a taxable-account projection is optimistic compared with a tax-deferred one.
Which calculator should I start with?
Start from the decision you are actually making rather than the product you have been sold. If the question is whether to pay more than the scheduled minimum, the extra-payment, home-equity and debt-consolidation calculators answer it from the same amortisation model. If the question is what a decision costs each month, the credit-card and student-loan tools lead with the schedule. If the question is when you can stop working, retirement and ROI are the relevant pair. Where two tools overlap, run both — the mismatch between their assumptions is the useful signal.
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Generate favicons, app icons and other web design assets right in your browser — every size is drawn locally and nothing is uploaded.
This space is reserved for a sponsor. Every tool on this site stays free and runs locally in your browser.