Systematic evaluation of dog behavior in animal shelters has been advocated as an essential component of addressing the behavioral needs of dogs in shelters and for helping make appropriate placement decisions. Yet there is little information available about the prevalence of behavioral responses observed in these evaluations. Conducting evaluations in a standardized fashion and collecting results in a centralized database would yield prevalence estimates of behaviors and common patterns, helping shelters make more informed decisions regarding in-shelter enrichment, behavior modification, and placement. The Match-Up II Behavior Evaluation, a standardized test battery, was developed based on analysis of 668 evaluations, follow-up survey results with owners of adopted dogs, and multiple rounds of applied testing and revision. In order to make the data collection as standardized as possible, we developed an online portal to allow users to enter data and automatically score results. Currently, there are 15 shelters actively using the Match-Up II Online portal amounting to 4,100 dogs. Of these, 36.7% displayed jumpy/mouthy behavior; 27.8% displayed fear of people, and 8.3% displayed food-related aggression. Using an online portal for collecting and scoring shelter dog behavior evaluations is feasible in real world shelter settings. Pooling of data from multiple shelters will allow initial estimates of prevalence of common behavioral responses to various sub-tests, thereby allowing shelters to plan appropriate resources for their canine populations. Moreover, these findings will help shelters identify and manage problematic behaviors of individual dogs before and after adoption thereby preventing unneeded euthanasia.