TakeoffMetric is a free set of construction calculators and estimating tools for people who have to order something: contractors, estimators and owners about to pay for a delivery of concrete, gravel or lumber. The main result of every calculator is a quantity you can order, rounded the way suppliers sell it: cubic yards with a waste allowance, bag counts and truck loads, not a decimal with four places.
The site is organized like a set of construction drawings. Each calculator is a sheet with a number and a discipline prefix taken from the US National CAD Standard convention: C for civil and earthwork, S for structural, A for architectural, P for plumbing, M for mechanical and G for general estimating. 26 sheets are live today, including concrete, rebar, footings, gravel, asphalt, roof pitch, board feet and duct.
Every sheet prints its formula, the assumptions behind it and the sources it was checked against. The drawing on the page is dimensioned from the same numbers as the result, and the material takeoff can be exported or printed, so a quantity can be checked line by line before an order is placed. Each sheet also carries a revision number that changes when the math changes.
TakeoffMetric also publishes original data. A benchmark of free online concrete calculators, which records the volumes they display for six fixed inputs next to an independently computed reference, is available on Mendeley Data under a DOI.
What it is not: TakeoffMetric is not written by licensed engineers and does not claim to be. Thicknesses, reinforcement and base depths shown on the site are ordinary US practice, not code requirements, and the building department, the engineer and the soils report always come first. The quantities are estimates for planning and ordering.
No sign-up is needed to use the calculators, and corrections sent to the contact address are published on a dated corrections page.
