Eye tracking can serve as a gateway to studying the mind. For this reason it has been adopted by a diverse range of scientific communities. With the improvement of the quality of head-mounted virtual reality devices (HMDs) over the past 10 years, eye tracking has been added to capture gaze in immersive environments. The use of HMDs with eye tracking is increasing significantly and so is the need for a toolbox enabling consensus about eye tracking methods in 3D. We present the Salient360! toolbox: it implements functions to identify saccades and fixations and output gaze characteristics (e.g., fixation duration or saccade directions), to generate saliency maps, fixation maps, and scanpath data. It also implements routines made to compare gaze data that were adapted to 3D. We hope that this toolbox will spark discussions about the methodology of 3D gaze processing, facilitate running experiments, and improve the gaze study in 3D. https:// github.com/ David-Ef/ salient360Toolbox CCS CONCEPTS • Software and its engineering → Software libraries and repositories; • Human-centered computing → Visualization toolkits; • Information systems → Extraction, transformation and loading.