About

What it is

Every calculator is a sheet, with a number and a discipline prefix taken from the US National CAD Standard convention used on real drawing sets: C civil & earthwork, S structural, A architectural, E electrical, P plumbing, M mechanical, G general & estimating. A sheet carries a title block with its revision, its formula version and the number of sources it was checked against, a dimensioned drawing, a material takeoff you can export, and the assumptions behind the number.

It is aimed at people who have to order something: contractors, estimators, and owners who are about to spend real money on a delivery. That is why the primary output is an order quantity rounded the way the supplier actually sells, not a decimal with four places.

Where it stands today

8 sheets are issued out of 17 in the set, across 18 planned silos. Sheets are published one at a time. A calculator that is listed but not issued has no page and no link: the registry that drives the navigation also drives the sitemap, so unfinished work cannot leak into search results.

Who writes it

TakeoffMetric is built and maintained by its operator. It is not written by licensed engineers and it does not claim to be. Formulas come from arithmetic and from published industry references, and every page says which ones. Where a decision needs an engineer, a soils report or a building official, the page says that instead of guessing.

How it is built

Static HTML, no framework on the client, one small custom element that upgrades a page that already works without it. No images, no third-party scripts, no fonts from someone else's server. The formulas are a separate, tested, unit-aware library, which is also why the same numbers can appear in a plan drawing, a section drawing, a takeoff table and a CSV without drifting apart.

Contact

Found a number that is wrong, or a case the sheet does not handle? That is the most useful message you can send. See corrections for how to report it and what happens next.