Magnetocaloric effect and order of transition in (La1−x Nd x )2/3(Ca1−y Sr y )1/3MnO3, prepared by conventional solid-state reaction, have been investigated. Using Banerjee criterion, we demonstrate first-order transition for ( J1) and ( J2 ) as well as second-order transition for ( J3 ), ( J4 ), and ( J5 ) samples. The ΔS M max is ranging between 9.18 Jkg−1 K−1 and 4.87 when Nd and Sr content changes leading to relative cooling power (RCP) varying between 330 and 229.35 J/kg. Both ΔS M max and the RCP are found sensitive to the disorder σ 2. The universal behavior obtained from ΔS variation curves confirmed the first-order transition for ( J1 ) and ( J2 ) samples and second-order transition for ( J3 ), ( J4 ), and ( J5 ) samples obtained by Banerjee criterion. All samples with second-order phase transition exhibit inhomogeneous character estimated from local exponent n.