What is a simple, free SOAP client (GUI)?

You can still use SOAPUI.

1. Download the installation script and save it on the disk.

2. then either

   • from a terminal

     cd /path-to-directory-where-you-downlaod-it
     sudo chmod +x soapUI-x32-4_0_0.sh
     sudo ./soapUI-x32-4_0_0.sh
     

   • Or if you don't like command you can do it graphically:

     1. Right-click on the downloaded file, select Properties, go to the Permissions tab and Allow to execute as a program.

        

     2. Once that is done double click on the .sh file and select 'Run in terminal' or Run

3. Then follow step by step instructions to finish the installation.

source

Alternatives

• Membrane SOAP Client is a generic SOAP client written in Java. It provides a dynamic form generator for SOAP requests.

  

  source

• You can use jmeter a 100% pure Java application designed to load test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other test functions. Jmeter is in the Ubuntu repositories.

  getting started