A method for automatic real-time performance intonation (ARPI) of electronic, digital, or computer-based musical instruments automatically adds the intonation characteristics of a variable-intonation instrument performance to an equal-tempered chromatic instrument performance. The method emphasizes the directional lead-in quality, upwards, or downwards, of certain notes in relation to the musical context. Notes, which are musically desirable to resolve upwards in a harmonic progression receive a slightly raised pitch, and notes that generally are resolved downwards receive a slightly lowered pitch. The method identifies major thirds and major sevenths in the harmonic context and raises their pitch slightly. It identifies minor thirds and minor sevenths in the harmonic context and lowers their pitch slightly. Fourth and fifth intervals are given a pure perfect tuning and octaves are made slightly wide. All is done automatically in real-time by identifying the harmonic context from a few preceding notes.