In pursuit of our mission to improve the profession of software development, Scrum.org offers many tools and resources free to the software development community. Two of these resources are the free Open assessments: Scrum Open and Scrum Developer Open.
The Scrum.org Open Assessments allow you to check your basic knowledge of Scrum and a number of software development practices and techniques that support building high-quality and high-value products in a Scrum Team.
These are invaluable tools for anyone preparing to take assessments granting Professional Scrum certification. More importantly, it's the starting point on your path to continuously improve your knowledge and skills.