Humane Research and Testing Act of 2021 This bill establishes the National Center for Alternatives to Animal Research and Testing within the National Institutes of Health to promote alternatives to animal research and testing and to reduce the number of animals used in such research and testing. In addition, federal departments or agencies and federally funded research entities that use animals for research and testing must develop plans to reduce the use of animals in their activities. They must also annually report the number of animals that they use to the center, and the center must make this information publicly available.