Pitch trainer · intervals
Sing an interval in tune
Choose an interval and a starting note. The page plays the two notes, you sing them back, and it shows what you sang and the size of the interval between them in cents.
The interval exercise
The microphone is off. Nothing on this page listens until you press Start microphone.
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- Off by
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- Frequency
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- Measured against
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- Clarity
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What you sang
| # | Asked for | You sang | Cents off | Heard | Result |
|---|
Nothing sung yet.
The exercise
Settings
A4 = 440.0 Hz
How the interval exercise works
Press Play the reference and listen. The microphone is not needed for that, and while the reference sounds the microphone’s readings are thrown away, so the page never grades its own tone.
Then start the microphone and press Sing it back. After a count-in of one note length, every note has a box on the grid and a slot of time. Sing each note while its box is lit. The slots do not wait: what you sang inside each slot is what is reported.
A random interval picks one of the 12 for you. The name stays on the screen: this page is for singing an interval you have been given. For finding a note by ear with nothing named, use pitch matching.
Reading the result
For each slot the page takes the readings from the middle of the slot, leaving out the first fifth and the last tenth where one note turns into the next, and reports their median as the note you sang. Cents off is counted from the note asked for, or from its nearest octave if Any octave counts is ticked. Heard is the share of the slot in which the page heard a pitch at all. Under 30% the slot is reported as not heard instead of being graded.
Under the table the page also gives the interval you actually sang: the distance in cents from your first note to your second, next to the distance asked for. You can sing both notes flat by the same amount and still sing the interval exactly, and the two figures let you see which happened.
The 12 intervals
An interval is the distance between two notes. The names below are the usual ones for distances of 1 to 12 semitones (Wikipedia, Interval (music)). The cents are those of equal temperament, 100 to the semitone (Wikipedia, Cent (music)), which is what the reference tones play and what the grading measures against. This is a measurement of pitch, not vocal coaching.
| Interval | Short | Semitones | Cents | Up from C4 | Down from C4 |
|---|---|---|---|---|---|
| Minor second | m2 | 1 | 100 | C4 – C♯4 | C4 – B3 |
| Major second | M2 | 2 | 200 | C4 – D4 | C4 – A♯3 |
| Minor third | m3 | 3 | 300 | C4 – D♯4 | C4 – A3 |
| Major third | M3 | 4 | 400 | C4 – E4 | C4 – G♯3 |
| Perfect fourth | P4 | 5 | 500 | C4 – F4 | C4 – G3 |
| Tritone | TT | 6 | 600 | C4 – F♯4 | C4 – F♯3 |
| Perfect fifth | P5 | 7 | 700 | C4 – G4 | C4 – F3 |
| Minor sixth | m6 | 8 | 800 | C4 – G♯4 | C4 – E3 |
| Major sixth | M6 | 9 | 900 | C4 – A4 | C4 – D♯3 |
| Minor seventh | m7 | 10 | 1000 | C4 – A♯4 | C4 – D3 |
| Major seventh | M7 | 11 | 1100 | C4 – B4 | C4 – C♯3 |
| Perfect octave | P8 | 12 | 1200 | C4 – C5 | C4 – C3 |
Sources
- Interval (music) — Wikipedia. Used for the names of the intervals of 1 to 12 semitones. Revision 1369352691 of 2026-08-14. Read 2026-09-28 (UTC). https://en.wikipedia.org/wiki/Interval_(music)
- Cent (music) — Wikipedia. Used for the cent: 100 to an equal-tempered semitone, 1200 · log2(f2 / f1). Revision 1376384857 of 2026-09-23. Read 2026-09-28 (UTC). https://en.wikipedia.org/wiki/Cent_(music)
Next: sing scales in tune, or watch your pitch live on the vocal pitch monitor.
How it measures, and what it keeps
The pitch comes from a detector that runs inside this page: the normalised square difference method of McLeod and Wyvill, tuned for a voice from C2 to D6. It was measured on 7,344 synthesised tones, not on recorded singers and not on your microphone; the method page has the tables and says what they do not cover.
The sound from your microphone goes to that detector and nowhere else: it is not recorded, stored or sent. This browser keeps three settings for the trainer’s pages, under labs.sing.a4, labs.sing.solfege and labs.sing.range. The musical facts (note names, cents, scales, intervals, voice types) are read from thirteen published articles, each listed on the method page with its revision and the date it was read.