New Compliance Test Tool Release for OPC UA V1.05.06
OPC Foundation announced the release of the OPC UA Compliance Test Tool (UACTT) with extended testing capabilities for OPC UA FX and Companion Specifications.
Scottsdale, AZ – November 20th, 2025 - The OPC Foundation is pleased to announce the upcoming release of the initial version of the OPC UA Compliance Test Tool (UACTT) supporting the OPC UA Specification Version 1.05.06. This release marks a significant step forward in providing robust and reliable testing capabilities for vendors, system integrators, and end users working with OPC UA-based products and solutions.
The OPC UA Compliance Test Tool can be used to test OPC UA Client, Server, Publisher, Subscriber and so-called Global Discovery Servers (GDS) products for compliance to the OPC UA specification. Over 2600 test scripts validate basic functionalities. This new Release allows testing semantics as defined in Companion Specification.
Benefits of using the UACTT
Ensures correct and consistent implementation of OPC UA specifications.
Improves interoperability between products from different vendors.
Detects issues early, reducing development time and cost.
Prepares products for successful OPC UA certification.
Increase overall product quality and customer confidence.
Extended support for Companion Specifications
The new UACTT release supports the latest enhancements in the OPC UA Core and OPC UA FX specifications, while significantly expanding automated test coverage for Companion Specifications.
It enables developers and integrators to validate information model implementations across 124 standardized Companion Specifications, including the harmonized models for Device Integration, UA for Machinery, and PA-DIM.
“The enhanced ability to test Companion Specifications directly within the CTT is a game-changer for developers, integrators and also End-Users. It allows them to verify the semantic correctness of their implementations and significantly reduces the time and effort required for integration,” says Alexander Allmendinger, Test Lab Manager of the European Certification Test Lab.
By validating both type definitions and instances, the CTT ensures that products correctly implement the intended information model semantics. This prevents integration issues early in the development and provides confidence that UA Clients can reliably discover and interact with all required elements defined in the companion specifications.
The new test scripts provide a direct and easily accessible benefit to early adopters for the time until the test cases have been created by the joint working group itself. The groups are encouraged to extend the testing coverage with enhanced modelling and functional testing of the companion specification.
User experience and real-world validation
The CTT’s intuitive user interface and detailed log messages provide immediate feedback on passed and failed test cases, helping developers quickly identify and resolve issues. This functionality also empowers end users to validate purchased products during commissioning, ensuring seamless integration into their systems.
The testing capabilities for Companion Specifications have already been validated with multiple sample servers and are currently being applied to real-world implementations. The release of the CTT with these features is scheduled for the end of this year and will be available to all users of the tool.
20 years of commitment to open standards
“The OPC UA version 1.0 became available on July 28th, 2006, and shortly thereafter in 2007 the OPC Certification Program and Test Labs have been introduced and the first OPC Lab has been established. Since 20 years the OPC Foundation is continuously optimizing the offerings: this time by enhancing the CTT to support for Companion Specification testing, we are reinforcing our commitment to open standards and interoperability. This release supports our mission to provide high-quality tools to the entire ecosystem—vendors, integrators, and end users alike,” says Stefan Hoppe, President and Executive Director of the OPC Foundation.
The UA Compliance Test Tool is available from the OPC Foundation website and free of charge for OPC Foundation Corporate Members.
