<p>This paper presents a comparative analysis between the cleavage fracture stress (CFS) model proposed earlier by the author and Chaouadi’s simplified model (CSM) for estimating the ASTM E1921 reference temperature, <i>T</i>₀, from Charpy V-notch (CVN) impact tests. Additionally, a new simplified parametric correlation is introduced for estimating <i>T</i>₀, drawing inspiration from the methodologies employed in the CFS and CSM models. Results show that while the brittleness temperature (<i>T</i>_D) based correlation found in literature gives the most accurate estimates of <i>T</i>₀, namely, <i>T</i>_QBT, for most steels, the CFS, CSM, and parametric methods produce estimates that fall within the same scatter band. The CFS model provides the most accurate estimates (<i>T</i>_Qcfs), followed by the CSM estimate (<i>T</i>_QCSM), and the parametric correlation estimate (<i>T</i>_Q41UYR). The CSM and parametric models are advantageous for their simplicity, relying on conventional Charpy transition data, whereas the CFS model and the brittleness temperature based correlation require instrumented Charpy test data and complex calculations (for the CFS model). The CFS and CSM models, though developed entirely by different routes, provide results that compare favourably with each other in terms of accuracy and less scatter, but the former is not as simple as the CSM model method.</p>