Seventh Chord Type Classifier
Classify complete root-relative seventh sets (including fully/half diminished and minor-major) independently of triads, collapsing octave doublings; incomplete/extra collections remain unrecognized.
Description
Seventh quality depends on the complete root-relative pitch-class set.
Seventh quality depends on the complete root-relative pitch-class set. Doublings do not create additional chord members.1
Enter 1–128 integer offsets 0–127. Reduce modulo12/deduplicate/sort and compare the seven supported four-tone patterns. Return label and highest class as seventh class when recognized; otherwise −1.
When to use Seventh Chord Type Classifier
Use Seventh Chord Type Classifier when you need to evaluate the supplied records under the calculation and evidence rules below. Incomplete or extra sets are unrecognized. No root, inversion or audio pitch extraction is performed.
Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.
How to use Seventh Chord Type Classifier and understand its results
- Enter the written notes, explicit grouping, pitch observations or supported chord tokens requested. Keep scientific octaves, accidentals and caller evidence consistent.
- Enter rootRelativeSeventhSemitones using the field table and calculation rules, then run the tool.
- Read seventhQualityLabel, seventhPitchClass. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| rootRelativeSeventhSemitones | Root relative seventh semitones | list of number | Required |
Enter 1–128 integer offsets 0–127. Reduce modulo12/deduplicate/sort and compare the seven supported four-tone patterns. Return label and highest class as seventh class when recognized; otherwise −1.
match exact major7,dominant7,minor7,half-diminished,dim7,minor-major7,augmented-major7 patterns Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| seventhQualityLabel | Seventh quality label | string |
| seventhPitchClass | Seventh pitch class | number |
{
"input": {
"rootRelativeSeventhSemitones": [
0,
3,
6,
10
]
},
"output": {
"seventhQualityLabel": "half-diminished",
"seventhPitchClass": 10
}
}Limitations and assumptions
Incomplete or extra sets are unrecognized. No root, inversion or audio pitch extraction is performed.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Chord Quality From Intervals Classifier: Tertian triad quality is defined by a complete root-relative pitch-class set. Octave doublings do not change the set. For a complementary task, use Sus Chord vs Triad Classifier: Suspended chord sets replace the third with a second or fourth. Complete pitch-class collections differ from a missing-third claim alone.
References
-
Seventh Chord Type Classifier — tool.io
Similar or alternative tools
- Chord Quality From Intervals Classifier
Tertian triad quality is defined by a complete root-relative pitch-class set. Octave doublings do not change the set.
- Sus Chord vs Triad Classifier
Suspended chord sets replace the third with a second or fourth. Complete pitch-class collections differ from a missing-third claim alone.