The ACL-IQ is a 5-item tool to quantify visual estimation of Anterior Cruciate Ligament (ACL) injury risk. The ACL-IQ was developed to overcome cost, time, and usability limitations associated with current injury risk screening procedures. The current study cross-validated the ACL-IQ against a larger representative sample of 428 individuals (214 general population and 214 exercise science/sports medicine professionals). The ACL-IQ revealed similar between-group discriminability (d =1.84) and range as previous investigations. Overall, regardless of group, domain-specific ACL knowledge and estimated cue validity were the best predictors of ACL-IQ performance (R=.50). Domain-general perceptual/cognitive tests and personality did not influence ACL-IQ above domain-specific factors.