About Make It Exact
Make It Exact publishes calculators that show their work. Every page states the formula it used, lets you change the assumptions it made, and names where its numbers came from — or says plainly that it does not know.
What this site refuses to do
Three rules decide what gets published here, and they cost us pages rather than earn them:
- No material constant without a dated, primary source. Geometry is ours to compute; a bag yield or a coverage rate belongs to whoever manufactures the product. Where published figures disagree — and they do — the calculator asks you for the number off the bag instead of picking a side. One common bag size was removed from the concrete calculator for exactly this reason.
- No default price. Competing calculators print a price per cubic yard. It is wrong for most readers on the day they read it and stale for the rest. This site asks for your quoted price or shows no cost at all.
- No option in place of an answer. A setting does not resolve an uncertainty, it moves it to someone who knows less than we do. Options exist here only where readers genuinely differ — the waste allowance, the units — never to avoid deciding something we ought to have researched.
The same reasoning keeps some subjects off the site entirely. Health and diagnostic questionnaires are not published here: the instruments are licensed, the stakes are somebody else’s health, and “exact” would be a promise nobody can keep — as the Bayes’ theorem calculator demonstrates about screening tests.
What “exact” means here
That the calculation is rigorous and its assumptions are stated — never that a quantity delivered to a site will match. A slab poured on uneven ground takes more concrete than any calculator predicts. Pages that produce estimates say so, and the waste allowance is shown as a separate figure rather than folded silently into the total.
How it pays for itself
Nothing yet — there is no advertising, no affiliate link, no paid placement and nothing to buy. When advertising is introduced it will sit after the answer rather than inside it, and it will never influence what a calculator computes or which sources it cites. This page will be updated the day that changes.
Corrections
If a number here is wrong, that is worth more to us than a new page. Write to [email protected] with the calculator and the figures you used. Publisher and registration details are on the legal notice, and the rules above are set out in full under how these calculators are built.