Disclaimer

CalcPerks publishes calculators covering money and health. Both are areas where a wrong number can cost someone real harm, so it is worth being direct about what these tools are and what they are not.

General information only

Everything on this site — the calculators, the worked examples, the explanations and the FAQs — is published for general information and educational purposes. It is written for a broad audience and cannot take account of your circumstances, because we know nothing about them. We never see your inputs; they stay in your browser.

This is not professional advice

Nothing on CalcPerks is financial, investment, tax, accounting, legal or medical advice. We are not your adviser, accountant, broker, lawyer or clinician, and using a calculator here does not create a professional relationship of any kind. No result should be treated as a recommendation to take, or avoid taking, any particular action.

Before you act on a number from this site — signing a loan, changing a repayment plan, altering your diet, or making any decision that matters — check it with a qualified professional who can look at your full situation.

Why our results are estimates

Our calculators use standard, published formulas, and we state which formula each one uses on its page. The mathematics is sound. The gap between our answer and your reality comes from everything the formula leaves out:

Simplifying assumptions. Most models assume a constant rate, a regular payment schedule, or an average body — real life rarely cooperates.
Rounding and day-count conventions. Institutions differ on how they round and how they count days in a period, which shifts figures by small amounts that compound over time.
Rules that vary by place. Tax rates, thresholds, statutory fees and consumer rules differ by country, state and even city, and they change without notice.
Individual factors. Credit history, contract terms, medical history, medication and genetics all move real outcomes away from a population average.

Currency and unit handling is another place to be careful: figures carry no implicit currency, and results only make sense if the values you entered were consistent.

Financial, tax and business calculators

Tools such as the mortgage, loan, auto loan, amortization, credit card payoff, retirement, salary, sales tax, VAT and inflation calculators produce illustrations, not quotes.

Interest rates, APR and the way interest is compounded vary between lenders, and the rate you are actually offered depends on your credit profile.
Real loans include costs we cannot know: arrangement and origination fees, insurance, property taxes, escrow, early-repayment charges and closing costs.
Tax tools apply the rate you enter. They do not know your local tax rules, brackets, allowances, exemptions or filing status, and they are not a substitute for tax advice or a tax return.
Investment and retirement projections assume a return you supply. Markets do not deliver steady returns, and past performance says nothing about the future.

Where figures conflict, the other party's figures govern.The number on your lender's offer, your bank's statement, your card issuer's terms or your tax authority's assessment is the authoritative one — not ours. Use our result to sanity-check theirs and to ask better questions, never to override them.

Health and fitness calculators

Tools such as BMI, BMR, body fat, ideal weight, calorie and macro, water intake, target heart rate, pregnancy due date and ovulation calculators are based on population-level formulas. They describe what is typical across large groups of people. They are not diagnoses, and they cannot tell you whether you personally are healthy.

BMI compares weight to height. It does not distinguish muscle from fat and misreads athletes, older adults, pregnant people and children. It is a screening signal, not a verdict on your health.
BMR, calorie and macro figures come from equations fitted to study populations. Individual metabolism varies substantially around those averages.
Body fat estimates from tape measurements are approximations with a meaningful margin of error compared with clinical measurement.
Pregnancy due date results are estimates from a standard cycle assumption. Very few babies arrive on the estimated date, and a dating scan from your midwife or doctor takes precedence.
Ovulation and fertile-window results assume regular cycles and are estimates only. Do not use this calculator as a method of contraception. Calendar-based prediction is not reliable birth control and offers no protection against sexually transmitted infections.

Never use this site to self-diagnose, to start or stop treatment, or as a reason to delay seeking care. If you have a health concern, speak to a doctor or qualified health professional. If you think you may be having a medical emergency, contact your local emergency services immediately — do not wait on anything you read here.

Links to other sites

We sometimes link to external resources such as tax authorities, standards bodies or research sources. Those sites are not under our control. We are not responsible for their content, accuracy, availability or privacy practices, and a link is not an endorsement of any product, service or opinion.

Advertising disclosure

CalcPerks is free to use and is supported by advertising, including Google AdSense. Advertising is what pays for building and hosting these tools.

We decide where ad slots sit on the page; we do not choose, review or endorse the individual ads shown in them, and the content of an ad is not controlled by CalcPerks. An ad appearing here is not a recommendation, and we make no promise about any advertiser's products, services or claims. Any transaction you enter into with an advertiser is strictly between you and them. Ads never influence which formula a calculator uses or what result it gives.

For how advertising cookies work and how to opt out of personalised ads, see our Privacy Policy.

Found something wrong?

If a result looks incorrect, tell us. Send the tool name, the values you entered and the figure you expected through the Contact page. We check every report, and if a calculator is wrong we fix it and re-verify it. See how we build and check our calculators for more on that process. Your use of this site is also subject to our Terms of Use.

Last updated: August 2026.