2-Carboxy-1-phenylethanaminium perchlorate

In the title compound, C9H12NO2+·ClO4−, an intramolecular N—H...O interaction results in the formation of a six-membered ring having a twisted chair conformation. In the crystal structure, intermolecular O—H...O, N—H...O and C—H...O interactions link the molecules into a network. A weak C—H...π interaction is also found.