In recent years self-tracking technologies have become widely adopted. Life-writing scholars have contributed to the burgeoning academic interest in this phenomenon and pointed to similarities between the diary and present-day self-tracking apps, wearables and our digital ‘data doubles’ resulting from networked technology. However, studies on self-tracking in historical diaries are rare. In this article, I focus on experiences of self-tracking in five Dutch diaries from the long nineteenth century (1780–1940). Self-tracking includes all sorts of ways in which people have turned their bodies, minds, and habits into data. I have constrained my analysis of self-tracking in diaries to two bodily aspects: firstly, masturbation in connection with sleeping habits and, secondly, the menstrual cycle and birth control. The diaries show that the ‘quantified self’ in effect often becomes the ‘qualified self’, because tracking data involves interpretation, identity meanings and storytelling. The most important link between self-tracking in the stories told, both in historical paper diaries and in present-day forms, is the discourse of ‘ableism’. Ability as a norm takes shape in the long nineteenth century with the diary as a key ‘technology of the self’ in which the responsible, self-governing individual monitors his or her own health and wellbeing.