Achievement of low-risk status is a treatment goal in pulmonary arterial hypertension (PAH). Risk assessment is often performed using multiparameter tools, such as the Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL) risk calculator. Risk calculators that assess fewer variables without compromising validity may expedite risk assessment in the routine clinic setting. We describe the development and validation of REVEAL Lite 2, an abridged version of REVEAL 2.0.To develop and validate a simplified version of the REVEAL 2.0 risk assessment calculator for patients with PAH.and Methods: REVEAL Lite 2 includes six non-invasive variables: functional class (FC), vital signs (systolic blood pressure [SBP] and heart rate), six-minute walk distance (6MWD), brain natriuretic peptide (BNP)/N-terminal prohormone of brain natriuretic peptide (NT-proBNP), and renal insufficiency (by estimated glomerular filtration rate [eGFR]) and was validated in a series of analyses (Kaplan-Meier, concordance index, Cox proportional-hazard model and multivariate analysis).REVEAL Lite 2 approximates REVEAL 2.0 at discriminating low, intermediate, and high risk for 1-year mortality in patients in the REVEAL registry. The model indicated that the most highly predictive REVEAL Lite 2 parameter was BNP/NT-proBNP, followed by 6MWD and FC. Even if multiple, less predictive variables (heart rate, SBP, eGFR) were missing, REVEAL Lite 2 still discriminated among risk groups.REVEAL Lite 2, an abridged version of REVEAL 2.0, provides a simplified method of risk assessment that can be implemented routinely in daily clinical practice. REVEAL Lite 2 is a robust tool that provides discrimination between patients at low, intermediate, and high risk of 1-year mortality.