The relations of order, complexity, and their balance with aesthetic appreciation have been an interest of inquiry for centuries. The literature in this research field is contradictory, however, disagreeing on the type and direction of the relation of order and complexity with aesthetic appreciation. Moreover, the relationship between order and complexity is a puzzling one as it seems to be both antagonistic and complementary. Few studies have investigated both order and complexity simultaneously, while also recognizing both constructs to have multiple aspects. Furthermore, those studies that investigated the role of order often reduced it to examining symmetry. Our online study will overcome these issues and will empirically test how order and complexity contribute to aesthetic appreciation using a controlled stimulus set. We created an Order & Complexity Toolbox for Aesthetics (OCTA) to easily generate stimulus sets that, once published as an open-source Python package, will grant other researchers in the field the ability to manipulate stimuli to desired degrees of order and complexity in a number of different stimulus dimensions (e.g., size, shape, color pattern, etc.). The aim of this study is to further investigate the interplay between order and complexity in relation to aesthetic appreciation by examining how both constructs contribute to aesthetic appreciation, and whether they do so in an independent or a joint fashion. Levels of perceived complexity, order, and aesthetic appreciation will be collected, while individual differences and their interactions with stimulus properties will be examined to systematically investigate their role in aesthetic appreciation