robotbenchmark is a web service with a cloud-based 3D robot simulation software that provides a series of robotics challenges to researchers and students. Robotics challenges, including a performance evaluation metrics, are provided to the users. Users can program simulated robots in Python and run the simulation to evaluate the performance of their robot controllers. A ranking of the best performing robot controllers is stored for each benchmark, including a simulation playback capability. Researchers are welcome to contact us to add more benchmarks to this cloud service. Participation is free of charge.