SAP2000 alternative

A free, open-source alternative to SAP2000, in your browser

Stabileo is free, open-source (AGPL-3.0) structural analysis software that runs in your browser, with no install, licence key or account. The solver is written in Rust and compiled to WebAssembly, so the model is solved on your own computer. Basic mode models, loads, solves and reads results for 2D and 3D frames and trusses; PRO mode, in development and open to everyone, adds slabs and walls, DXF and IFC import, code loads and member checks.

When it is a good alternative

  • Analysing frames, trusses and buildings without paying for a licence or installing anything, on any operating system with a modern browser.
  • Checking results from another program: Stabileo is compared with seven other finite-element programs, and every line of its code can be read.
  • Teaching and learning: it shows the stiffness method step by step.
  • Checking steel and concrete members to AISC 360, EN 1993-1-1, AISI S100, ACI 318, EN 1992-1-1 and Argentina’s CIRSOC codes, in PRO mode.

When it is not yet

  • If you need the range of design codes and the decades of track record of an established commercial program: PRO mode is still in development.
  • If your firm requires software independently reviewed by a licensed engineer: that review has not happened yet.

Frequently asked questions

What is the best free alternative to SAP2000?

It depends on what you use SAP2000 for. For browser-based 2D and 3D frame, truss and shell analysis with nothing to install, Stabileo is free and open source. For scripted nonlinear research analysis, OpenSees is the long-standing open-source option.

Can I use Stabileo instead of paying for a SAP2000 or ETABS licence?

For analysis of frames, trusses and many buildings, and for member checks to AISC 360, ACI 318, the Eurocodes and CIRSOC, yes, for free. For the full range of design codes and a long production track record, commercial programs still offer more; Stabileo’s PRO mode is in development.

Is Stabileo really free?

Analysis (Basic and PRO) is free for everyone. Code design is free while it is in development, and after that stays free for public universities and for those who take part in its development. The AI assistant will be paid. The code is AGPL-3.0.

Does it run on Mac or Linux?

Yes. It runs in any modern browser, on any operating system.

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