About STCalculator

A number is more useful when you can see where it came from. We bring the inputs, units, method and result together so you can explore a calculation and understand its assumptions.

Our library spans mathematics, health, finance, science, sport, construction and everyday life. Most calculators are available without an account.

Calculator pages may include a formula, worked example, interactive diagram, frequently asked questions and links to related tools. The available detail depends on the calculator and its subject.

Changing a unit should change the display, not the underlying quantity. Rounding should make a result easier to read without disguising an important boundary or limitation. These are the principles that guide our updates.

An optional member account lets you create favorite lists and save calculation scenarios. You can return to a saved setup without having to enter the same values again.

Keep saved scenarios free of patient identifiers, confidential financial records and other sensitive information. A workspace is a convenience for calculations, not a medical record or a secure document vault.

We distinguish a reference from a review. A source explains a method or standard. An expert review is a separate assessment of a particular page.

Where a review is published, the page identifies the reviewer and links to their profile. It does not imply that every calculator has been independently reviewed, or that a source institution endorses STCalculator.

Expert articles and page reviews follow separate editorial approval workflows. Read the scope of a review and the limitations of the calculation before relying on a result.

If an answer looks wrong, tell us the calculator URL, inputs, units and expected result. A reproducible example is more useful than a screenshot on its own.

We assess reported issues and update methods, wording or usability where needed. Important medical, financial, legal and safety decisions still need the relevant professional or primary authority.