VRrec: A zero-coding open-source VR body-motion capture tool for behavioral research.

We present VRrec, an open-source, motion-tracking and recording tool for PC-based virtual reality (VR). The tool addresses a persistent gap in VR-based experimental research by enabling real-time capture of head, hand, and optional body-tracking data without the need to code. VRrec runs discreetly in the background, collecting positional and rotational data as researchers engage participants with third-party VR applications. This design lets researchers use flexible paradigms that leverage off-the-shelf VR content, eliminating the need to build or modify custom software. However, because VRrec does not read application-level events or object states from the target VR software, it does not directly support paradigms that require synchronization with in-app events or distances to dynamic virtual objects or avatars. VRrec still allows manual event marking for contextual annotation. The resulting data are stored as plain text, which can be imported into various analysis pipelines to derive behavioral metrics in fields such as social psychology, rehabilitation, and consumer research. Evaluations show consistent and stable recording performance with minimal impact on system resources, while also indicating some limitations for study designs that require millisecond-accurate timing precision. By streamlining VR motion data acquisition, VRrec broadens the range of feasible VR study designs and reduces technical barriers, making VR-based behavioral research more accessible. Both the source code and the executable version of VRrec are freely available on GitHub.