Section properties

A, I, S, Z, r, J and the centroid for a published AISC, SSMA, NDS or CMU section, a custom cold-formed profile, or a solid rectangle, tee or circle — each one from the same engine the paid module runs, with the document it came from named.

Choose a shape class

Each class is answered by a different engine, and the result names which one answered. Choose one and the fields it needs appear — nothing else does, because a phone has room for one shape at a time.

What this calculator does

  • Six shape classes, six engines, and the result says which one. AISC Shapes Database v16.0 · SSMA/SFIA cold-formed · a custom lipped C or track by the mid-line method · NDS Supplement dressed sizes and LVL · CMU wall sections · and solid rectangles, tees and circles from first principles. Nothing here is a second implementation: every number comes out of the engine a paying customer's module calls.
  • A catalog shape gives you the catalog's numbers. An AISC designation, an SSMA/SFIA designation and a CMU wall width are looked up and reported as published, with the document named beside them. Only a section you dimension yourself — a custom cold-formed profile, or a solid rectangle, tee or circle — is computed here, and it says so.
  • It refuses rather than approximates. A section too thick for the mid-line method, a profile the kernel does not really build, an AISC family no design check branches on, an untabulated CMU width, a tee's torsion constant — each is declined by name, with the reason, instead of coming back as a plausible number.
  • Geometry only, and that is the whole point. No capacity, no DCR, no classification, no buckling signature. Those need a material, a code chapter and a limit state this page never asks you for — so nothing here is a partial answer dressed as a whole one.

What this calculator does not do

  • No capacity. Geometric properties only. No capacity, no DCR, no classification, no unbraced-length curve, no buckling signature — and that is not a teaser. Geometry is not capacity, and every one of those needs a material, a code chapter and a limit state this page does not ask you for.
  • One section. One section at a time. No built-up assembly beyond what a catalog already publishes, no composite section, no transformed section.
  • No arbitrary polygon. No arbitrary closed polygon. A general cross-section is meshed and integrated by the section FE engine, which is what steel_section_01 advertises for built-up shapes — a closed form cannot reach it and this page will not pretend otherwise.
  • No thick thin-wall. The custom cold-formed path is the MID-LINE method. A section thicker than the published range it is verified against is refused with the numbers, never returned as a mid-line answer.
  • No document. No stamped report, no PDF, no saved project. The numbers are whole; the document is what the paid module is for.

Need the capacity, not the geometry?

Geometry is not capacity, and capacity is what the paid modules compute: φMn against unbraced length, P-M-M interaction surfaces, width-to-thickness classification, DSM buckling signatures, and the arbitrary-polygon section engine for a built-up shape no closed form reaches.

See the plans