New standard tuning (NST) is an alternative tuning for the guitar that approximates all-fifths tuning. The guitar's strings are assigned the notes C2-G2-D3-A3-E4-G4 ; the five lowest open strings are each tuned to an interval of a perfect fifth {(C,G),(G,D),(D,A),(A,E)}; the two highest strings are a minor third apart (E,G).

Guitar tunings are the assignment of pitches to the open strings of guitars, including classical guitars, acoustic guitars, and electric guitars. Tunings are described by the particular pitches that are made by notes in Western music. By convention, the notes are ordered and arranged from the lowest-pitched string to the highest-pitched string, or the thickest string to thinnest, or the lowest frequency to the highest. This sometimes confuses beginner guitarists, since the highest-pitched string is referred to as the 1st string, and the lowest-pitched is the 6th string.