About WhichCalc
WhichCalc helps you explore calculations, understand the method, and check the assumptions behind a result. Our tools cover finance, health, mathematics, and everyday planning.
Who builds WhichCalc
WhichCalc is developed and maintained by MammiriWeb. This is an independent calculation website, with a public contact address at info@whichcalc.com. It is not a government agency, bank, lender, healthcare provider, or school, and a result is not an official decision from any of those organizations.
The United States is the default region. Our Australian collection uses separate local units, currency, and assumptions. Choose the appropriate version before using a region-dependent estimate.
How to check a calculation
Start with the calculator catalog. Documented tools include instructions, a formula, a worked example, topic-specific answers, and links to references. Follow the example with the same inputs, then change one value to understand its effect. Sources support the stated method or data; linking a source does not mean that its publisher has endorsed WhichCalc.
Percentage rates, dates, units, rounding, and regional rules can change the output. A worked example explains a particular scenario, rather than promising that the same outcome applies to everyone. Read a page’s assumptions and content date alongside its result.
What our results mean
Arithmetic tools answer a mathematical question. Planning tools estimate an outcome under assumptions that may differ from your situation. Financial projections do not predict market returns or confirm eligibility for a product. Health estimates do not diagnose a condition or prescribe treatment. Entertainment tools are labeled as such and should not guide personal decisions.
Check important figures against the relevant institution or a qualified professional. See our disclaimer for the limits of the service.
Corrections and maintenance
If a formula, source, input label, or result appears incorrect, email info@whichcalc.com with the page URL, sample inputs, expected output, and the reference you used. Use invented examples rather than private financial or medical records. This helps us reproduce an issue and compare the calculation with its documentation.
We prioritize documented tools in the catalog. A calculator whose guide is incomplete can remain available at its existing address while its documentation is improved. Adding more tools is secondary to explaining the ones people can already use.
Privacy and funding
The tools are free to use without an account. Most arithmetic runs in your browser; some tools may retrieve external data such as exchange rates. Analytics and advertising are separate from the calculation, and the website may display Google AdSense ads. Advertising does not constitute a recommendation of an advertiser or its products.
Read our privacy policy for cookies and third-party services, and our terms for use of the site.
Our Mission
To provide easy-to-use, accurate, and free online calculators for everyone. We believe that access to quality calculation tools should be available to all.
Our Vision
To make everyday calculations easier to understand. A useful result should come with enough context to tell you when it applies, what it leaves out, and how to check it.