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SAP2000 is a general-purpose structural analysis and design program from Computers and Structures, Inc. (CSI). Engineers and researchers use it to model a structure in 3D, run linear or nonlinear analyses, check members against design codes and produce reports from a single interface. This page summarises what the program does, which analysis types and file formats CSI documents, and how it relates to CSI’s other programs. Facts come from CSI’s own product pages, read on 2026-11-08.
What SAP2000 is
CSI describes SAP2000 as “structural analysis and design” software and says the SAP name is associated with analytical methods developed over more than 45 years. The product page presents modeling, analysis, design and reporting as one integrated workflow in a single interface, with customizable window and toolbar layouts and a DirectX-based 2D/3D drafting and selection environment. Its mesh tools can merge independently defined meshes across frame, shell and solid objects.
Who makes it and what it covers
CSI publishes SAP2000 alongside ETABS, CSiBridge, SAFE and other structural programs. Within the program, the SAPFire Analysis Engine provides multiple 64-bit solvers, eigen and Ritz analysis, and parallel processing across multiple processors. Code-based design is listed for steel frame, concrete frame, cold-formed steel and aluminum frame structures; CSI keeps the full list of supported design codes on a separate design-codes page.
SAP2000 is offered in four levels: Basic, Plus, Advanced and Ultimate. CSI’s comparison page lists model size as limited to 1,500 nodes in one case and as having no practical limit in another; CSI’s compare-levels page is the place to see which level carries which capability.
Analysis types and design checks
CSI’s features page lists the following analyses. The table restates its wording and does not rank them.
| Analysis | What CSI states |
|---|---|
| Linear static | Supported, including multi-step static cases for vehicle, live and wave load patterns. |
| Modal | Eigen or Ritz analysis. |
| Response spectrum | Supported. |
| Time history | Linear and nonlinear; nonlinear direct-integration time history and Fast Nonlinear Analysis (FNA) are both listed. |
| Nonlinear static and buckling | Nonlinear static buckling analysis is listed. |
| P-Delta | Can be applied once under gravity or sustained loads for linear cases, or per load combination. |
| Staged construction | Includes creep and shrinkage per CEB-FIP and ACI 209R. |
On the modeling side, CSI lists a 3D object-based graphical environment, rigid and semi-rigid diaphragm constraints, interactive database editing of model tables, frame elements with biaxial bending, torsion, axial and biaxial shear deformation, cables, tendons, 8-node solids, link and spring supports, fiber hinges and nonlinear layered shells.
Design is integrated with analysis. CSI lists automatic steel sizing, reinforced-concrete design, and steel, concrete, aluminum and cold-formed code checks under American, Canadian and international standards. Steel member size optimization uses auto-select lists, which need at least two defined sections. Cold-formed C, Z and hat sections and straight or curved aluminum girders are among the listed section types.
Importing and exporting models
For a project that passes through several programs, the exchange formats matter as much as the solver. CSI documents these routes:
| Direction | Formats and tools listed by CSI |
|---|---|
| Export and import | Revit, Tekla Structures, AutoCAD DXF/DWG, BricsCAD, CIS/2, IFC (2×3 and 4), IGES, SDNF |
| Database export | Microsoft Access |
| Import | FrameWorks Plus, STAAD, STRUDL |
| Plugins | CSiXCAD; CSiXRevit (bi-directional); a Tekla link (round-trip) |
CSI also documents an application programming interface usable from VBA, VB.NET, C#, C++, Visual Fortran, Python and Matlab, and from Excel. It is available for ETABS, SAP2000 and CSiBridge, with cross-product tools supported from ETABS v18, SAP2000 v21 and CSiBridge v21. Scripted models are easier to rerun and review, which connects to the practices described in our entries on computational reproducibility and computational environment.
Where to find the sign-in
CSI states that Standalone and Network licenses are no longer supported and that they are converted to Cloud Sign-in licenses. Account access is through CSI’s Customer Center, linked from the product page.
Strengths and limits
- Documented strengths: one interface from modeling to reporting; a wide list of analysis types, including nonlinear time history and staged construction; code checks for steel, concrete, cold-formed steel and aluminum; exchange formats including IFC and CIS/2; an API usable from several languages.
- Scope: CSI sells separate programs for buildings (ETABS), bridges (CSiBridge), floor systems (SAFE) and performance-based design (Perform3D). SAP2000 is CSI’s general structural analysis and design program.
- Level dependence: model size and other capabilities are tied to the level (Basic, Plus, Advanced, Ultimate).
Other CSI programs
| Program | CSI’s one-line description |
|---|---|
| SAP2000 | Structural analysis and design |
| ETABS | Building analysis and design |
| CSiBridge | Bridge analysis, design and rating |
| SAFE | Analysis and design of floor systems |
| Perform3D | Performance-based design of 3D structures |
| CSiPlant | Pipe stress analysis and design |
| CSiCol | Design of reinforced concrete columns |
When structural software appears in a paper or report, cite the program and version so others can reproduce the analysis; see the FAIR4RS and software citation principles and our guide to Better Scientific Software.
FAQ
What is SAP2000 used for?
CSI describes it as structural analysis and design software: modeling, analysis, code-based design and reporting in one interface.
Who makes SAP2000?
Computers and Structures, Inc. (CSI), which also publishes ETABS, CSiBridge, SAFE and Perform3D.
Which materials does its design module check?
CSI lists steel frame, concrete frame, cold-formed steel and aluminum frame design; the codes are listed on CSI’s design-codes page.
Can SAP2000 exchange models with Revit or IFC tools?
CSI lists Revit, Tekla Structures, AutoCAD, CIS/2 and IFC (2×3 and 4) among its import and export routes.
Are Standalone and Network licenses still supported?
CSI states they are no longer supported and are converted to Cloud Sign-in licenses.
Sources
- CSI, SAP2000 product page, read 2026-11-08.
- CSI, SAP2000 features, read 2026-11-08.
- CSI, SAP2000 compare levels, read 2026-11-08.
- CSI, CSI products, read 2026-11-08.
