Quantification has driven the advancement of civilisation and facilitated significant progress in science, engineering, and the humanities. Despite its widespread success, quantification now presents a philosophical challenge: can the use of numbers or measurements to describe phenomena adequately address the complexity of human existence? Existential critique maintains that quantification, while effective for observable phenomena, does not capture qualities such as authenticity, consciousness, freedom, and intrinsic value. These dimensions are rooted in individual and subjective experience. Efforts to quantify these aspects result in a category error, reducing unique human experiences to objects, distorting meaning, and fostering alienation. Furthermore, quantification reduces ethical responsibility to numerical terms, thereby diminishing the moral and personal dimensions of experience. This paper draws on existentialist thinkers (Sartre, Heidegger, Camus) and phenomenologists (Husserl, Merleau-Ponty) to propose an ethics of quantification that explicitly recognises the limits of measurement and prioritises existential understanding. The strengths and limitations of quantification, including its contributions to social progress and science, are critically examined. Ultimately, recognising the boundaries of quantification is argued to be essential for preserving meaningful human understanding.