Display omitted •Simple patient data can evaluate the probability that LVH is of hypertensive origin.•Machine learning algorithms achieve this with high accuracy.•Online calculators have been made publicly available. Left ventricular hypertrophy is often associated with hypertension, which is not necessarily the cause of hypertrophy. Non-hypertension-related aetiologies often have a strong impact on patient management, and therefore require a thorough and careful workup. When considering all left ventricular hypertrophies, even the mild ones, the number of patients who need a workup increases drastically. This raises the need for a tool to evaluate the pretest probability of the origin of left ventricular hypertrophy. To predict the hypertensive origin of left ventricular hypertrophy using machine learning on first-line clinical, laboratory and echocardiographic variables. We used a retrospective single-centre population of 591 patients with left ventricular hypertrophy, starting at 12mm maximal left ventricular wall thickness. After splitting data in a training and testing set, we trained three different algorithms: decision tree; random forest; and support vector machine. Model performances were validated on the testing set. All models exhibited good areas under receiver operating characteristic curves: 0.82 (95% confidence interval: 0.77–0.88) for the decision tree; 0.90 (95% confidence interval 0.85–0.94) for the random forest; and 0.90 (95% confidence interval: 0.85–0.94) for the support vector machine. After threshold selection, the last model had the best balance between its specificity of 0.96 (95% confidence interval: 0.91–0.99) and its sensitivity of 0.31 (95% confidence interval: 0.17–0.44). All algorithms relied on similar most influential predictor variables. Online calculators were developed and made publicly available. Machine learning models were able to determine the hypertensive origin of left ventricular hypertrophy with good performances. Implementation in clinical practice could reduce the number of aetiological workups needed in patients presenting with left ventricular hypertrophy.