ExtendSim vs FlexSim
ExtendSim
extendsim.comFlexSim
flexsim.comSide by side
| Figure | ExtendSim | FlexSim |
|---|---|---|
| Price from | $833.33/mo | — |
| Free plan | — | — |
| Free trial | Yes | Yes |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 10 | 1 |
| Spec score · Simulation Software | 9.0 (#2) | 7.8 (#8) |
| Spec score · Business Simulation Software | 9.1 (#2) | 7.8 (#10) |
| Company history | Imagine That Inc. was founded in 1987 to develop Extend and ExtendSim, and ANDRITZ Inc. acquired the ExtendSim family in 2024. | FlexSim says it began in 1993 and that Autodesk acquired FlexSim Software Products in November 2023. |
| Founded | 1987 | 1993 |
| Headquarters | ANDRITZ Inc. is listed at 13560 Morris Road, Suite 1250, Alpharetta, GA 30004 USA. | San Francisco, California, USA |
| Optimization | ExtendSim includes an integrated evolutionary optimizer, sensitivity analysis and scenario experimentation tools. | FlexSim integrates with OptQuest for scenario optimization with variables, constraints, and multiple objectives. |
| Purpose | ExtendSim simulates processes to help decision-makers assess opportunities for improvement and determine system configurations. | FlexSim is 3D discrete-event simulation software for modeling and improving existing and proposed systems. |
| Support | The annual Maintenance & Support Plan covers download and installation help, troubleshooting, updates, upgrades and refreshed activation keys. | Technical support is included for customers with active maintenance or subscription, and the support page aims for a first response within two working days. |
| Trial | The trial runs for 30 days from first launch and is limited to the person who downloaded it. | The Autodesk trial intake page lists a 30-day trial from the date of download and Windows 64-bit as the available platform for FlexSim 2027. |
Plans
ExtendSim
- Analysis RunTime (Individual)$495, paid once
- ExtendSim CP (Individual)$995, paid once
- ExtendSim DE (Individual)$3,495, paid once
- ExtendSim Pro (Individual)$4,995, paid once
- ExtendSim Cloud Subscription (up to 4 instances)Priced on request
- ExtendSim Cloud (up to 4 instances)$10,000 a year
- ExtendSim Cloud Subscription (up to 32 instances)Priced on request
- ExtendSim Cloud (up to 32 instances)$25,000 a year
- OEM license$50,000 a year
- OEM License$50,000 a year
In their own words
ExtendSim
ExtendSim is process simulation software for decision-makers assessing improvement opportunities and system configurations. It supports customizable modeling logic, hierarchical subsystems, interactive user interfaces and exploration of design options. Features include reusable custom blocks, model hierarchies, simulation animation, 35 built-in distributions and statistical analysis tools. Data exchange options include Excel, ODBC and ADO databases, FTP and text files; Scenario Manager can export results to JMP or Minitab. ExtendSim Pro adds discrete-rate and reliability block diagramming capabilities to DE, while DE adds message-based discrete-event architecture to CP. It is a Windows application, with web also listed as a platform. Standard licenses require 64-bit Windows 10 or Windows 11; ARM configurations are not officially supported. Mac use requires installing Windows with an emulator such as Parallels or Boot Camp. The trial lasts 30 days from first launch and is limited to the downloader; it disables Multicore Analysis, watermarks models and cannot run on virtual machines. Individual license options are one-time purchases, with first-year Maintenance & Support included; CP costs $995, paid once, DE $3,495, paid once and Pro $4,995, paid once.
FlexSim
FlexSim is 3D discrete-event simulation software for modeling and improving existing or proposed systems. Its realistic 3D graphics visualize system behavior, while drag-and-drop controls let users place objects and resources and import CAD drawings or custom 3D objects. Model-building options include a Standard Object Library, Process Flow activity blocks, FlexScript, and C++ integration. For analysis, FlexSim offers charts, graphs, data tracking, and spreadsheet export. OptQuest integration supports scenario optimization using variables, constraints, and multiple objectives. The Experimenter compares scenarios, distributes replications across CPU cores, and supports report generation and performance measures. Data can be imported and exported through Excel and SQL connectors, with FlexScript APIs for files, sockets, and HTTP requests. The Emulation tool supports Modbus, OPC DA, OPC UA, and certain manufacturer-specific PLC connections; some require an Emulation license. FlexSim is listed for Windows and web, with desktop deployment. Pricing is on request; the free Express trial plan has limits including 30 3D objects and 35 Process Flow activities.