About materiacalc

Ten editions, one engine, and a rule about not guessing. materiacalc publishes material calculators in ten languages, and each edition is written for its own market instead of translated from one original — different worked examples, different sack sizes, different things worth warning about. Where a local figure could not be checked, it is left out rather than filled in.

How materiacalc calculates

One calculation engine serves the whole site. It works in SI units and converts only for display, so a figure entered in feet and the same figure in metres give the same answer. Countable outputs — bags, tins, boxes — always round up: a spare bag of mortar costs a few euro, while running short halfway through a pour costs a cold joint and a day.

Assumptions and sources

Every result lists the constants it used, with the date each was last checked. If your tin or your sack says something different, type that in — the answer follows your number, not ours.

ACI CODE-332-20, Code Requirements for Residential Concrete — plus the state and local codes that actually govern the permit.

What these tools will not do

These tools size a quantity, not a structure. Slab thickness, reinforcement and load bearing are design decisions that depend on the ground and the loads, and nothing here has seen your site. Where a local figure could not be verified, materiacalc marks it as unverified instead of guessing.