About CalculatNow

We publish calculators across finance, real estate, health and fitness, math, and everyday life. Every one of them is free, works without an account, and runs in your browser so your numbers never leave your device.

A calculator on its own is not much use if you cannot see how it reached its answer, so each tool is paired with a plain language explanation of the formula behind it and a list of the sources we relied on. Our aim is that you leave understanding the result, not just holding it.

Accuracy is the only thing that makes a calculator worth using. We take four steps on every tool we ship.

• We start from a named, documented formula rather than inventing one, and we say which formula a page uses.
• We take data from the primary authority. Tax and benefit figures come from the IRS, the Social Security Administration, and state departments of revenue. Health formulas come from the CDC, the World Health Organization, the published U.S. Navy body fat method, and peer reviewed research. Math tools use standard published methods.
• We separate the math from the interface and cover it with unit tests, including against worked examples published by the authority itself, so a redesign can never quietly change a result.
• We date anything that goes stale. Where a calculator depends on figures that change, the page states the tax year or shows when it was last reviewed.

We cite sources so you can check us rather than trust us. We link to the authority itself, not to a summary of it. We do not publish filler articles written to attract search traffic, and we would rather ship one calculator that is right than five that are approximately right.

When we get something wrong, we fix it and we do not pretend otherwise. If you find an error, please write to us. Reports of calculation errors go to the top of the queue.

CalculatNow is free to use. There is no paywall, no account, no trial, and no feature held back for a paid tier. The site carries no advertising and no third party tracking, and calculations happen on your device rather than on our servers. Our Privacy Policy sets out exactly what that means in practice.

We are not a bank, lender, insurer, investment adviser, tax preparer, law firm, medical practice, or real estate brokerage, and we are not licensed to advise you. Our results are estimates produced from the numbers you enter, and they cannot account for your circumstances.

For anything that matters, speak to a professional who is qualified in the relevant field and in your jurisdiction. Our Disclaimer explains this in detail, category by category.

Found a bug, spotted an error, or want a calculator we have not built yet? Email support@calculatnow.com. We read everything.