A　compact　cat　swarm　optimization　algorithm　(cCSO)　was　proposed　in　this　paper.　it　keeps　the　same　search　logic　of　cat　swarm　optimization　(CSO),　i.e.　tracing　mode　and　seeking　mode,　on　the　other　hands,　cCSO　inherits　the　main　feature　of　compact　optimization　algorithms,　a　normal　probabilistic　vector　is　used　to　generate　new　individuals,　the　mean　and　the　standard　deviation　of　the　probabilistic　model　could　lead　cats　to　the　searching　direction　in　next　step.　Only　a　cat　is　adopted　in　the　algorithm,　thus,　it　could　run　with　modest　memory　requirement.　Experimental　results　show　that　cCSO　has　better　performance　than　some　compact　optimization　algorithms　in　some　benchmark　functions　test.　The　convergence　rate　is　also　a　highlight　among　compact　optimization　algorithms.　©　Springer　International　Publishing　AG,　part　of　Springer　Nature　2018.