The perception of agency in human-robot interaction is crucial as robots become more capable and social. However, there is no widely accepted or consistent method to measure perceived agency. The authors define perceived agency and develop a psychometrically validated scale to measure it. They compare their scale (PA) with two existing scales (PA-R and Korman) and find that their scale fits empirical data better. The scale is also validated by showing a hypothesized relationship between perceived agency and morality. The study uses Rasch analysis to construct a unidimensional scale, ensuring that all components (raters, items, and entities) are on the same logit scale. Experiment 1 generates items for the scale, while Experiment 2 evaluates the scale's performance and compares it with other scales. Experiment 3 validates the scale by examining the relationship between perceived agency and willingness to save entities, finding a strong negative correlation. The results suggest that the PA-R scale is the most effective measure of perceived agency.The perception of agency in human-robot interaction is crucial as robots become more capable and social. However, there is no widely accepted or consistent method to measure perceived agency. The authors define perceived agency and develop a psychometrically validated scale to measure it. They compare their scale (PA) with two existing scales (PA-R and Korman) and find that their scale fits empirical data better. The scale is also validated by showing a hypothesized relationship between perceived agency and morality. The study uses Rasch analysis to construct a unidimensional scale, ensuring that all components (raters, items, and entities) are on the same logit scale. Experiment 1 generates items for the scale, while Experiment 2 evaluates the scale's performance and compares it with other scales. Experiment 3 validates the scale by examining the relationship between perceived agency and willingness to save entities, finding a strong negative correlation. The results suggest that the PA-R scale is the most effective measure of perceived agency.