Perceived Legibility and Aesthetic Pleasingness of Light and Ultralight Fonts

In the last five years the use of light and ultralight fonts has become the new norm in the user interface design of most digital products. Our previous research, based on performance measures, showed that lightweight fonts have negative effects on text legibility and cognitive load when performing word search tasks. However, objective data and subjective perceptions of legibility and aesthetic appeal of fonts do not always correspond. In this paper we present the results of a subjective evaluation study of four variations of the Helvetica Neue typeface (ultralight, light, normal and bold) presented with high vs. low contrast and positive vs. negative polarity. 63 subjects volunteered in a pairwise comparison survey aimed at evaluating the preferences of respondents with regard to perceived legibility and aesthetic pleasingness of sixteen combinations of font weight, contrast and polarity. The results suggest that users of different ages evaluate the legibility of ultralight font as being very low, but younger users may perceive ultralight fonts as more aesthetically appealing than do older users. Based on our study, we provide recommendations on the use of lightweight fonts in user interface design.