People use calendars for a long time but stand-alone electronic calendars came along only with personal computers, while shared online calendars are here only for less than two decades. The paper investigates impact of personality (following the Big Five Inventory framework) on use of shared online calendars. Data were gathered in the Czech Republic. The sample consisted of university students. Age, gender, and type of student job were used as control variables. With regards to the results, gender, openness to (cognitive) experience, and type of student job influence the adoption. It is male, more open to experience, and working student who use shared online calendars more.