Abstract An ab initio study of aluminum-like calcium is presented. The calculations are performed within the configuration interaction method in the basis of transformed radial orbitals with a variable parameter. Relativistic effects are accounted for within the Breit–Pauli approximation. Energy spectra, transition characteristics and lifetimes of excited levels of configurations 3s 23p, 3s3p 2, 3s 23d, 3p 3, 3s3p3d, 3p 23d, 3s 24s, 3s 24p, 3s 24d, 3s 24f, 3s3p4s, and 3s3p4p are obtained. The results are compared with available experimental and theoretical data.