Revit is the go-to BIM software for standard commercial buildings and architecture firms. OpenBuildings, on the other hand, shines on massive infrastructure. Like airports, transit networks, and heavy industrial facilities.

AECOsim was Bentley’s original name for its multidiscipline building design tool. In 2018 they rebranded it to OpenBuildings Designer to match the naming used across OpenRoads and OpenRail.

Old AECOsim documentation stayed in place but moved under the new brand. So both names point to the same software now, just from different eras. Since people still search both terms, this guide uses them interchangeably.

Now once you understand that difference, it makes perfect sense why both platforms thrive side by side despite covering similar BIM ground. Here is how they actually stack up when it comes to tools, daily workflows, job markets, and real-world performance.

Table of Contents

What is Revit?

Autodesk Revit software is used for running a full BIM process. It contains components that carry relational information about themselves and stay connected to each other via one central database. These components are walls, beams, doors, etc.

When you edit one component in your floor plan, Revit updates it in the other sections or elevations or schedules automatically that are tied to that wall.

According to 6sense report, Revit has around 38% of the BIM and architectural design software market. And over 21,000 customers across 10 countries. This is why Revit often shows up as default requirement in BIM job postings.

What is AECOsim?

OpenBuildings Designer handles architectural, structural, mechanical, and electrical work inside one application. With built-in clash detection so teams can coordinate systems without switching tools.

The structural difference from Revit is in how the data gets managed. Revit centralizes everything in a single project database. OpenBuildings uses what Bentley calls a federated approach. Distributed teams can work on models and drawings of any size at the same time. Each discipline owns its own piece of the shared dataset.

It also folds in tools that Autodesk sells separately: energy analysis, solar and shadow studies, and photorealistic rendering through LumenRT come built into the core product. For firms handling sustainability compliance alongside design, that means fewer tools to license and learn.

OpenBuildings sits at just 0.06% market share in the same category, per 6sense report.

Read more: BIM vs CAD

What are the Key Differences between Revit and AECOsim

Aspect	Autodesk Revit	Bentley OpenBuildings Designer
Primary Focus	Building design across architecture, structure, and MEP, optimized for single-building projects	Multidiscipline building and infrastructure design, built to scale across large, geographically distributed teams
Market Share	38.19% of the BIM and architectural design software category	0.06% of the same category
File Handling	Native RVT format. Exporting to DWG or IFC strips out embedded data, leaving flat geometry	Native DGN format, readable by more third-party tools. Exchanges data in IFC, COBie, RealDWG, Revit Family RFA, and SketchUp SKP
Ecosystem Integration	Connects to Autodesk Construction Cloud, Navisworks, and Dynamo, though cross-tool sync issues are common	Integrates with ProjectWise for ISO 19650-based delivery, iTwin for digital twins, and LumenRT for real-time visualization
Geolocation	Uses a 0,0,0 model origin, which makes real-world geolocation harder to set up	Supports direct geolocation and can reference live GIS data into the design context

If you are already in Autodesk’s ecosystem, it makes sense to adopt Autodesk Revit. Because you are already familiar with the ecosystem, adoption becomes easier.

But for AECOsim or OpenBuildings Designer that becomes hard. The interface takes longer to learn if you’re coming from Autodesk. But you do get native support for a much wider range of file formats. Plus an easier time managing projects spread across different locations.

The pricing of Revit is ₹1,92,340/year per user (₹16,029/month if paid annually). If your need is a monthly-only plan, then the cost will be ₹23,600/month.

The cost of AECOsim or OpenBuildings Designer is ₹1,75,317/year per user. It comes bundled with credits that you can redeem for training or expert consulting.

When to Choose Autodesk Revit

You should choose Revit if you’re working on multi-disciplinary projects that need coordination across teams. Architectural, structural, or MEP teams. It stands as the stronger choice for any project with mandate of BIM standards.

Revit also makes sense simply because of where the jobs are. With such high market share and the largest customer base in the category, most firms hiring for BIM roles expect at least working Revit knowledge from day one. If your goal is broad employability you should invest in Revit.

When to Choose Bentley OpenBuildings Designer (AECOsim)

You should choose OpenBuildings Designer if your projects require a federated data model more than a centralized one. Its DGN-based file format is readable by a wider range of tools than Revit’s in-house RVT file standard. And its native integration with ProjectWise, iTwin, and GIS data makes it a stronger fit for asset lifecycle management on large, multi-vendor projects.

The UK’s HS2 project has been built in OpenBuildings. The project teams chose this because of its strength at large scale. A smaller, detail-focused build would lean toward Revit instead.

Given its 0.06% market share, learning OpenBuildings Designer is more of a deliberate, employer-driven choice rather than a general-purpose default. Most professionals will not encounter it unless a specific project or company requires it. So it makes sense as a second skill layered on top of Revit rather than a starting point.

Read more: Autodesk Construction Cloud Software Guide

Where Can You Learn AECOsim and Revit?

For OpenBuildings Designer, Bentley’s own LEARN Server is the primary resource. For Revit, Autodesk provides its own video training series and certifications for Revit learners. Focused specifically on Revit workflows and not general CAD tutorials.

But beyond those are structured courses for learning BIM. BuildAmbit’s Full-Stack BIM Professional Course for civil engineers is built around exactly that kind of project-based training.

What This Program Offers

Program Structure

7 Months duration
13 industry-focused modules covering end-to-end BIM workflows
5 studio-based learning stages to simulate real project environments
90+ hours of live, instructor-led sessions
Real-world capstone project executed with RSP Design India
Hands-on portfolio development support
Personalised career guidance
100 percent placement assistance

Core Tools & Software Training

Autodesk Revit
OpenBuildings Designer
Civil 3D
Tekla Structures
Navisworks
Dynamo
Autodesk Construction Cloud
ETABS
InfraWorks

Conclusion

Revit and OpenBuildings Designer solve overlapping problems with different architectures, one centralized and dominant, the other federated and specialized for scale.

For most professionals building a general BIM career, Revit’s market share makes it the higher-leverage first skill, and BuildAmbit’s Full-Stack BIM Professional Course for Civil Engineers is built to get you there.

Explore What Shapes Real Careers in the AEC Industry

Full-Stack BIM Professional Course for Architects

Full-Stack BIM Professional Course for Civil Engineers

Full-Stack BIM Professional Course for MEP Engineers

Explore What Shapes Real Careers in the AEC Industry

Full-Stack BIM Professional Course for Architects

Full-Stack BIM Professional Course for Civil Engineers

Full-Stack BIM Professional Course for MEP Engineers