SoapUI is an open-source web service testing application for service-oriented architectures (SOA) and representational state transfers (REST). Its functionality covers web service inspection, invoking, development, simulation and mocking, functional testing, load and compliance testing. A commercial version, SoapUI Pro, which mainly focuses on features designed to enhance productivity, was also developed by Eviware software. In 2011, SmartBear Software acquired Eviware.

SoapUI was initially released to SourceForge in September 2005. It is free software, licensed under the terms of the European Union Public License.[4] Since the initial release, SoapUI has been downloaded more than 2,000,000 times.It is built entirely on the Java platform, and uses Swing for the user interface. This means that SoapUI is cross-platform. Today, SoapUI also supports IDEA, Eclipse, and NetBeans.

SoapUI can test SOAP and REST web services, JMS, AMF, as well as make any HTTP(S) and JDBC calls.