Bentley Systems API
Bentley's iTwin Platform offers cloud REST APIs at api.bentley.com with OAuth 2.0, self-serve app registration, and the open-source iTwin.js SDK. The catch: engineering data must first be ingested from DGN and DWG files into an iModel via connectors before the APIs see anything.
Frequently asked questions
Bentley Systems scores A on the API Report Card. Bentley's iTwin Platform offers cloud REST APIs at api.bentley.com with OAuth 2.0, self-serve app registration, and the open-source iTwin.js SDK. The catch: engineering data must first be ingested from DGN and DWG files into an iModel via connectors before the APIs see anything.
Bentley Systems has a workable official integration path. Most engineering teams can build against it directly. Open API: self-serve, documented, with SDKs
Bentley Systems, Incorporated (Exton, PA; NASDAQ: BSY) is an infrastructure-engineering software company founded in 1984 by the Bentley brothers (Keith, Barry, Greg, Ray, Scott).
Construction is the closest single Supergood vertical, but Bentley's true footprint is infrastructure engineering, specifically the planning, design, and construction delivery of public-works infrastructure rather than the building-construction-centric world of Procore and Autodesk Construction Cloud. A highway engineer at AECOM opens OpenRoads Designer (MicroStation-based) to draft the geometry of a new interchange, generates profiles and cross-sections, references LiDAR survey reality meshes from ContextCapture/iTwin Capture, and publishes deliverables through ProjectWise to the state DOT client.
Very high in infrastructure engineering, lower in general CAD. Bentley reports 42,000+ accounts across 189 countries with $1.38B ARR (mid-2025) growing 11.5% YoY, 91% recurring revenue, and 109% net dollar retention.
Bentley software is the system of record for the engineering design, project delivery, and as-built data underlying the world's infrastructure: every state DOT highway alignment, profile, cross-section, right-of-way line, drainage design, and structures plan (OpenRoads + OpenBridge + MicroStation + ProjectWise); every major bridge design package (OpenBridge Modeler + STAAD + RM Bridge); every transmission line in a large fraction of the world's electric utilities (PLS-CADD/PLS-POLE/TOWER); every geotechnical analysis on tunnels, dams, foundations, and underground structures at the world's largest civil engineering firms (PLAXIS); every hydraulic model of municipal water distribution and wastewater systems for thousands of utilities (WaterGEMS/SewerGEMS/StormCAD/HAMMER); every offshore platform structural model at oil/gas majors (SACS); 4D construction sequencing and field-execution data for major capital projects (SYNCHRO 4D + SYNCHRO Field); asset performance, inspection, and digital-twin operating data for owner-operators (AssetWise + iTwin Experience); subsurface geoscience models for mining and energy (Seequent Leapfrog + GeoStudio); and the engineering Common Data Environment holding transmittals, deliverable reviews, markup cycles, digital signatures, and as-built records for many of the world's largest capital projects (ProjectWise + ProjectWise 365).
Legacy desktop core, modern cloud perimeter.
The iTwin Platform is genuinely modern, but the underlying engineering data still lives in DGN/DWG/IFC files that must first be ingested via iTwin Connectors and Synchronization into an iModel before the REST APIs see anything, for customers whose CAD files live on ProjectWise on-prem datasources, file shares, SharePoint, or engineer laptops, the iTwin surface is empty until they invest in connector setup and ongoing synchronization. Trial iTwin Platform subscriptions cap at 5,000 API calls/hour, which is restrictive for any non-trivial integration; moving to higher quotas requires upgrading to a paid iTwin Platform subscription whose pricing is consumption-based and not fully transparent on the developer portal. Full sourced list under Sources below.
Common alternatives include Autodesk (AutoCAD, Civil 3D, Revit, InfraWorks, Navisworks, ACC), Trimble (Tekla, SketchUp, Quadri, Trimble Connect, Vianova Novapoint), Nemetschek (Allplan, Vectorworks, Graphisoft Archicad, Bluebeam, Solibri, Risa), Hexagon (Bricsys BricsCAD, Leica reality capture, Smart Build/Plant, Intergraph CADWorx), Dassault Systèmes (CATIA, 3DEXPERIENCE), Oracle Aconex / Primavera P6 / Unifier. Graded alternatives appear under "More from the report card" below.
Grades measure one thing: can a customer's engineering team get their own data out programmatically? We check six things (whether a real API exists, how access is gated, data coverage, auth quality, docs and developer experience, and stability) and roll them into a letter grade. Grades get re-verified, and they only move on evidence.