The present technology, in general, relates to antimicrobial and biocidal compositions, for example bucket dilutable biocidal compositions, and the various applications and/or processes of utilizing them as hard surface disinfectants and/or cleaners. The biocidal composition of the present technology comprises hydrogen peroxide, a quaternary ammonium compound, an appropriate acid and an amine oxide in specific concentrations to provide a 5 minute or less microbial contact kill time for at least one biocidal target.