Given the vision and life-threatening course of retinoblastoma (RB), it has become a significant heritable childhood cancer to screen for. To recommend surveillance, risk must be estimated and genetic testing plays a vital role. However, genetic tests vary based on phenotype, sample availability, and laboratory analysis performance. RB genetic subtypes are referred to as: familial, nonfamilial heritable and sporadic. With no access to genetic testing, clinicians may rely on clinical features and phenotype, to estimate risk. Clinically, it is known that all bilateral cases are a result of germline mutation. There are some unilateral cases that are germline but not yet manifested as bilateral. To create the tool, the authors utilised data relating to: age, phenotype, genotype and relationship data. The authors refer to various papers on how they obtained estimates for unilateral RB and unaffected carriers’ risks. The authors also link to a website of their tool for use and recommend it for regions where access to specialised ocular oncology care is limited. There was no mention of testing the tool’s predictive ability on a sample so it is difficult to comment on the robustness. Nonetheless, RB screening remains an important tool in ophthalmology for catching cases early and saving vision. This research offers a free online tool to add to the literature.