Standards
Editorial Policy
How calculator pages are written: one question per calculator, explanations that match the calculation, and no filler.
- Last updated
One question per calculator
Each calculator answers one clearly defined question on one page. Variations of the same question — a different unit, a different unknown — are handled as modes of that calculator rather than as separate near-identical pages.
What an explanation must contain
- What the calculator computes, stated before you are asked to enter anything.
- The formula or method, in language that matches whether the result is exact or an estimate.
- The meaning of every input and output, the assumptions and the edge cases.
- Worked examples that demonstrate the method with numbers you can check by hand.
- No filler written only to make a page longer.
When a calculator is published
A calculator is published only when its formula is tested, its worked examples reproduce, its edge cases are handled with a clear message, and the page works with a keyboard, a screen reader and a small screen.