The structural, electronic and optical properties of the cubic RbMF3 perovskites (M = Be, Mg, Ca, Sr, Ba) have been investigated using the full -potential linearized augmented plane wave (FP-LAPW) method. The exchange and correlation potential was applied using the generalized gradient approximation for calculating the structural properties In addition, the modified Becke-Johnson (TB-mBJ) potential was used for calculating the electronic and optical properties. It was found that the lattice constant increases while the bulk modulus decreases with the change of cation (M) in going from Be to Ba in the RbMF3 perovskites (M = Be, Mg, Ca, Sr, Ba). The reflectivity and absorption properties were also studied using the mBJ method to understand the inter -band transitions and their possible applications in absorption devices in the UV-region. (C) 2017 Elsevier B.V. All rights reserved.