Abstract Two automatic backfat measurement devices (the New Zealand Hennessy & Chong Fat Depth Indicator (FDI) and the Danish Meat Fat Automatic (MFA) probe) were compared with the Optical Intrascope (OI) as alternative devices to predict P 2 backfat thickness (65 mm from the dorsal mid-line at the level of the posterior edge of the head of the last rib) in pig carcass classification schemes. Prediction equations of P 2 backfat thickness (mm) taken on the cold carcass (cold P 2) were developed for two operators who made independent hot carcass P 2 measurements (hot P 2) with the O1, FDI and MFA on each of 114 carcasses. The OI and FDI were found to be of equivalent precision in predicting cold P 2 with the same operator (residual standard deviation, RSD = 1·29 and 1·30, respectively). The MFA was significantly ( P < 0·05) less precise (RSD = 1·81). Between operator measurements of hot P 2 with the FDI (RSD = 1·17) had significantly ( P < 0·05) less variation compared with the OI and MFA (RSD = 1·27).