Money & Finance Calculators

One category, seven shelves, the same honest arithmetic

Money questions nearly always reduce to a handful of mechanical ideas: interest compounds, loans amortise, tax applies in brackets and inflation quietly rescales everything. The money category collects over seventy calculators across seven shelves, Mortgages & Property, Loans & Debt, Saving & Investing, Retirement & Pensions, Tax, Pay & Business and Spending, and every one of them is free and shows its working: the schedule, the formula, the year-by-year table, not just a final figure. This page maps the territory so you can find the right tool first time.

Borrowing: mortgages, property and every other loan

The Mortgages & Property shelf runs from the first affordability check to the final payoff. Its flagship is the Mortgage Calculator, which turns price, deposit, rate and term into a payment, a full amortisation schedule and a payoff date; around it sit the House Affordability Calculator for the price ceiling, the Rent vs Buy Calculator for the question before the question, country-specific tools for UK and Canadian mortgages, and the Refinance Calculator for restructuring later.

The Loans & Debt shelf generalises the same machinery. The Loan Calculator and Amortization Calculator handle any fixed-rate loan; the APR Calculator and Interest Rate Calculator expose the true rate that fees and points create beyond the quoted one; and the Auto Loan Calculator and Student Loan Calculator apply the mechanics to their own quirks, from trade-in equity to the UK's 9%-above-threshold repayment system. On the way out of debt, the Debt Payoff Calculator runs the avalanche and snowball orders side by side on your actual debts, the Credit Card Calculator shows why minimum payments take so long, and the Debt-to-Income Ratio Calculator reports the figure lenders will judge you by.

Growing money: compounding, returns and what a figure is really worth

The Saving & Investing shelf is built around one idea, compound growth, viewed from different angles. The Compound Interest Calculator is the plainest statement of it, splitting a future balance into what you contributed and what compounding added. The Savings Calculator points the same maths at a goal and returns a date; the Investment Calculator solves for whichever piece is missing, the end amount, the contribution, the years or the required return.

Two tools on this shelf keep the others honest. The Inflation Calculator converts money between years using the real US CPI-U record, a reminder that a projected balance decades away is not worth its face value. And the Average Return Calculator separates the arithmetic mean of yearly returns from the geometric mean, which is the compounding-honest one; quoting the former when the latter applies is how returns get overstated. For appraising a project or business decision rather than a fund, the IRR Calculator and Present Value Calculator carry the textbook time-value-of-money toolkit, with the Finance Calculator as the five-key generalist behind them all.

Retirement: building the pot, then draining it well

The Retirement & Pensions shelf splits the problem into accumulation and decumulation. On the way up, the 401(k) Calculator projects a balance split into your money, the employer match and growth, with 2026 IRS limit warnings built in; the IRA Calculator and Roth IRA Calculator do the same for individual accounts, including the 2026 contribution limits and income phase-outs. The general Retirement Calculator then asks the two-part question that matters: what does the pot grow to, and how long does it last once you draw an income from it?

On the way down, the Annuity Payout Calculator works the level income a pot supports, the RMD Calculator applies the SECURE 2.0 age rules to this year's required minimum distribution, and the Social Security Calculator compares claiming at 62, 67 and 70 with real break-even ages. Anyone weighing a defined-benefit scheme or a lump-sum offer against monthly income has the Pension Calculator for exactly that comparison.

Tax, pay and the price on the shelf

The Tax shelf states its tax year on every page, currently US 2026 figures where US rules apply. The Income Tax Calculator works federal tax bracket by bracket and shows the difference between your marginal and effective rates, a distinction that dissolves most bracket myths on its own. The Sales Tax Calculator and VAT Calculator both add tax on and, more usefully, pull it back out of an inclusive total, including the common back-out mistake people make by subtracting instead of dividing. The Marriage Tax Calculator and Estate Tax Calculator answer their narrower questions with the same bracket machinery.

On the Pay & Business shelf, the Salary Calculator converts between hourly, weekly, monthly and annual pay, and the Take-Home Paycheck Calculator turns a gross salary into net pay per payday with 2026 federal withholding, Social Security and Medicare shown line by line. Small-business arithmetic lives here too: the Margin Calculator keeps margin and markup from being confused, the Commission Calculator handles splits and tiers, and the Depreciation Calculator runs four accounting methods on the same asset. The small Spending shelf finishes the category with the Budget Calculator, which tests your income split against the 50/30/20 guideline, and the Discount and Percent Off calculators for what a sale price genuinely saves.

Working one real problem across several tools

Real decisions rarely stay on one shelf, and the tools are built to hand off to each other. Take a common one: you have spare cash each month and a mortgage. The Mortgage Payoff Calculator tells you the interest an overpayment saves; the Compound Interest Calculator tells you what the same money might earn invested; the Income Tax Calculator reminds you which of those outcomes is taxed. Or take a pay rise: the take-home tool shows what actually lands in your account, the budget tool reallocates it, and the 401(k) tool shows what diverting part of it into the match is worth by retirement. The habit worth building is to run the same pot of money through the competing tools before committing it; the comparison is usually more informative than any single answer.

Questions people ask

Where should I start if I am new to all of this?

With whichever number is currently causing you stress, but two tools repay everyone: the Budget Calculator, because every other decision depends on knowing what is left over each month, and the Compound Interest Calculator, because compounding is the mechanism behind savings, debts, pensions and mortgages alike.

Are the tax figures up to date?

Each tax page states the year it uses on the page itself; the US federal tools currently run 2026 figures, including the $15,000,000 estate tax exemption and the 2026 retirement contribution limits. When rules change, the pages change, so trust the year printed next to the result rather than assumptions.

Why do so many of these calculators show a schedule or table rather than one number?

Because the single number is usually the least informative part. A loan's monthly payment hides where the interest sits; a projected pension hides how sensitive it is to the return assumption. The schedule is where you see the mechanism, and seeing the mechanism is what lets you change the outcome.

Do the calculators handle currencies other than dollars?

The arithmetic of interest, amortisation and compounding is currency-neutral, so most tools work in whatever currency you think in. The exceptions are the country-specific pages, such as the UK and Canadian mortgage tools and the US tax pages, which say plainly which country's rules they implement.