An array sensing scheme for the differentiation of small peptides and their phosphorylated analogues is introduced. The technique involves a series of receptors created by appending random peptides to a C-3v symmetric scaffold that binds phosphomonoesters. Five specific peptide sequences were selected through a screening technique. In addition to cross reactivity being created by the peptides in the receptors, three metal ions and three OH indicators are used to create a suite of 45 indicator displacement assays. The colorimetric data from the 45 sensing ensembles is collected in a 96-well plate reader, and linear discriminant analysis gives patterns resulting in 100% classification of the peptides. The approach demonstrates a generalizable principle to create pattern-based recognition protocols for complex analytes.