What is the major thirteenth interval?
The major thirteenth is the compound form of the major sixth, carrying that interval's warm, bright quality to the top of the chord extension stack. In jazz theory, the thirteenth is the final extension—beyond the 13th, you've used every note in the scale. A dominant 13th chord (such as G13) contains the root, third, fifth, seventh, ninth, eleventh, and thirteenth, though in practice musicians omit certain notes (typically the fifth and eleventh) to avoid muddiness.
The natural (major) thirteenth works beautifully over both dominant and major chord types, adding a sweet, singing quality to the top of the voicing. Unlike the darker minor thirteenth (♭13), the natural 13th feels resolved and warm, making it ideal for endings, turnarounds, and passages where harmonic richness is desired without added tension.
Harmonic character
The major thirteenth brings the major sixth's sweet consonance to the top of complex chord voicings. When voiced well, the 13th sits above the other extensions like a crown, adding brightness without weight. Jazz pianists often voice 13th chords by placing the thirteenth as the highest note, where it sings clearly above the harmonic foundation.
- Compound equivalent: major sixth + octave
- Consonance: Consonant, warm
- Common chord context: Dominant 13th, major 13th, minor 13th
- Genre associations: Jazz, soul, funk, big band
Where you'll hear it
The 13th chord is a signature sound of big band jazz and soul music. Count Basie's orchestra frequently ended arrangements on lush 13th chords, and the sound became associated with swing-era sophistication. In funk and soul, dominant 13th chords provide the rich, complex harmonies behind artists like Stevie Wonder and Earth, Wind & Fire. The chord's combination of dominant tension and sweet extension creates the perfect balance for groove-based music.
Jazz guitarists like Wes Montgomery and Joe Pass made extensive use of 13th voicings, which sit naturally on the guitar's fretboard. Piano trio jazz frequently features 13th chords in comping patterns, where the thirteenth adds color and movement to otherwise static harmonies. In contemporary music, the 13th chord appears in neo-soul, gospel, and even sophisticated pop arrangements where composers seek harmonic richness without the tension of altered extensions.
Practice ideas
Start with a dominant seventh chord and add the major sixth an octave above the root to create a simple 13th voicing. Practice common jazz voicings for 13th chords: on piano, try root-7th-3rd-13th (left hand root, right hand the rest) in all keys. Compare the major thirteenth with the minor thirteenth to hear how one semitone shifts the character from bright warmth to dark tension. Listen to big band recordings and identify the 13th chords that typically appear at phrase endings and final cadences.