A few people have been asking us recently what factors influence SOA and Web Service test phase estimation. We’ve gathered some thoughts here for you on this topic. Firstly, you’re going to need a tool to execute your tests. The power and capabilities of the tool will greatly influence how long the testing will take. If the tool is cheap (or free), like some open-source offerings, testing estimation can be a fraught process. There can be so many unknowns with free test tools that the margin of error around your estimations will have to be very wide. The more established and powerful the tool is, the more confidence you will have around your estimations.