How to hear and sing every interval
Intervals are the vocabulary of melody. Here is each one — how it looks on the stave, how it sounds, and a reliable way to find it with your voice.
What an interval is
An interval is the distance between two notes. Each one has a number and a quality. The number comes from counting letter names, including both ends: C up to E spans C–D–E, three names, so it is a third. The quality — major, minor, perfect — says exactly how wide, measured in half steps: a major third is four of them, a minor third is three.
For a singer, intervals matter for one blunt reason: steps read themselves, and every leap is an interval you either know or guess. The difference between a reader and a guesser is a vocabulary of about a dozen sounds.
Reading intervals at sight: the geometry trick
Before your ear does anything, your eye can do half the work, because interval numbers are pure staff geometry:
- Odd-numbered intervals (3rd, 5th, 7th) sit the same way — both notes on lines, or both in spaces.
- Even-numbered intervals (2nd, 4th, 6th, octave) sit opposite ways — one on a line, one in a space.
So: line to the very next line, or space to the very next space, is a third. Line to a space with one line skipped in between is a fourth. Line to line with a whole line skipped is a fifth. It becomes as fast as reading.
Hearing intervals: measure from do
The most durable way to learn interval sounds is not song snippets — it is the scale you already own. Each note of the major scale sits a known interval above the tonic, so singing do up to any syllable is interval practice:
The anchor table
Song anchors work because you already sing these intervals perfectly — you just did not know their names. Use whichever anchors you actually know; the solfège column is the one that lasts.
| Interval | Half steps | In solfège | Ascending anchor |
|---|---|---|---|
| Minor 2nd | 1 | mi–fa, ti–do | The Jaws theme |
| Major 2nd | 2 | do–re | “Happy Birthday” (the first move), “Frère Jacques” |
| Minor 3rd | 3 | mi–sol, la–do | “Greensleeves”; downward: “Hey Jude” |
| Major 3rd | 4 | do–mi | “Oh, When the Saints” |
| Perfect 4th | 5 | do–fa, sol–do | “Amazing Grace”, “Here Comes the Bride” |
| Tritone | 6 | fa–ti | “Maria” from West Side Story; “The Simpsons” |
| Perfect 5th | 7 | do–sol | “Twinkle, Twinkle”, the Star Wars theme |
| Minor 6th | 8 | mi–do (up) | The theme from Love Story |
| Major 6th | 9 | sol–mi (up) | “My Bonnie Lies Over the Ocean”, the NBC chimes |
| Minor 7th | 10 | sol–fa (up) | “Somewhere” from West Side Story; the original Star Trek theme |
| Major 7th | 11 | do–ti | Scarce in tunes — sing the octave, settle down a half step |
| Octave | 12 | do–do | “Somewhere Over the Rainbow” |
Anchors are scaffolding, not the building
One honest caveat. Song anchors give you an interval out of context, and melodies never work that way — in a real line, the fourth you sing is coloured by the key around it. So use anchors to acquire a sound, then immediately practice the same interval inside a key: sing do–fa, not just the first two notes of “Amazing Grace”. The syllables carry the context with them; the song does not.
There is also a beautiful shortcut: one well-sung triad contains six intervals between its tones. That trick has an article of its own.
Do not forget the way down
Descending intervals are not the same skill in reverse — they need their own practice, and most singers have far weaker anchors for them. The scale helps again, because from the upper do the counts flip: do down to ti is a minor 2nd, do down to la a minor 3rd, do down to sol a perfect 4th, and do down to fa a perfect 5th. Sing do–la–do, do–sol–do and do–fa–do until falling feels as certain as climbing. It matters more than it seems: descending lines are where most pitch drift happens, and a singer who lands falling intervals precisely has removed the commonest cause of going flat.
Where to practice
Intervals stick when they arrive inside real melodies at the right grade. The NSM Method introduces leaps in strict order — thirds and the tonic triad before fourths and fifths — and the classic books are full of lines built almost entirely from triad leaps. Sing them in the studio and every leap you miss gets marked, which tells you precisely which intervals still need anchoring.