The present description relates to computer-implemented monitoring of monoclonal quality of cell growth, which is specifically applicable for the development of cell lines for the manufacturing of biopharmaceuticals. In one aspect a computer-implemented method is provided comprising: acquiring (ST10) a sequence of images (10) of a cell culture taken at different times during cell growth; processing (ST20) each image in the sequence of images to identify cell locations of cells in the cell culture; determining (ST40) for at least some of the images in the sequence of images the number of cells from the identified cell locations; determining (ST30) for at least one image in the sequence of images a spatial distribution of cells from the identified cell locations; evaluating compliance of the determined numbers of cells and the determined spatial distribution of cells with predetermined evaluation conditions being characteristic of monoclonal growth; and assessing and outputting a monoclonal quality indicator based on the evaluated compliance with the predetermined evaluation conditions.