The music interval calculator helps you determine the interval between two notes. You can choose from sounds in nine octaves and find the simple and compound name for any distance greater than an octave.
Intervals are one of the basic concepts of music theory. They are the building blocks of scales and chords, which in turn make up melodies and harmonies. Understanding and recognising them is important for musicians, as it makes it easier to play by ear, write melodies, communicate with other musicians, and understand more the complex ideas in music theory.
In the text below, you'll find a music intervals chart, and an set of instructions on how to use the music interval calculator. You'll learn what's the smallest musical interval, how to find interval quality, and how to find the distance between two notes, like from F to C.
Music interval  definition
A musical interval is the distance between two notes, which can also be described as the difference in pitch between two sounds. In physical terms, it is the ratio between the vibrational frequencies of notes.
Notes in music theory are sounds with determined frequencies. In English speaking countries, sounds in the C major scale (the white keys on a piano) are named with the first seven letters of the Latin alphabet:
C, D, E, F, G, A, B
Another common system for naming these sounds is solfège, which uses the syllables:
Do, Re, Mi, Fa, Sol, La, Si
Intervals may be counted in semitones. A semitone is the smallest unit of a musical distance that is commonly used in Western music. It is the distance between any two notes on adjacent keys (on a piano) or frets (on a guitar).
What is an octave?
Let's have a look at a piano keyboard:
On white keys we have the sounds C, D, E, F, G, A, and B. You can see that after B, you have another C, then D, and so the pattern repeats.
So, how do we differentiate between two Cs if we need to? We use the scientific notation  we add a number next to the letter, so we have C1, C2, C3, etc.
The interval (distance) between two notes, e.g., between C1 & C2 or F3 & F4, is called an octave. When we go an octave up, we double the frequency. For example:
A4 = 440 Hz
A5 = 880 Hz
A6 = 1760 Hz
Accidentals in music
We've covered the white keys, but what about the black ones?
We use the sharp "♯" and flat "♭" signs, along with the letters, to designate the sounds on the black keys. Sharp raises the note by a semitone (the smallest musical interval), while a flat lowers it by one.
The black key between C and D can be called C# or Db. C# and Db are the same sound, but which name you should use depends on the musical context.
If we play each note on a piano one by one from left to right, we get 12 tones which make up the chromatic scale:
C C#/Db D D#/Eb E F F#/Gb G G#/Ab A A#/Bb B
In this scale, the distance between any two adjacent notes is one semitone. E and F
and B and C
are the two pairs of white keys which don't have a black key between them, as they are a semitone apart anyway.
Musical intervals chart
Ok, this is the exciting moment where you learn the names of the intervals!
The smallest musical interval (not counting a unison, which is where the notes are the same, e.g., between C1 and C1) is the minor second. It's equal to one semitone, so a minor second is, for example, between G and G#. If you go from C to D, you will go up by a tone (two semitones), which is known as a major second. Below you can see the names of the intervals up to and including an octave and the corresponding number of semitones.
*A tritone is also called an augmented fourth or a diminished fifth.
How to use the music interval calculator?

Choose the first note and its octave.

Choose the second note and its octave.

At the bottom of the music interval calculator, you'll see what's the interval between the two notes. If you want to know the number of semitones and tones that make up the interval  switch the
advanced mode
.Note:

Intervals larger than an octave are called "compound intervals". They can be thought of as a certain number of octaves + the remaining interval.

For intervals with between 1328 semitones, you'll see both the simple and the compound name.

Intervals with more than 28 semitones (major seventeenth) will only have a compound name, as they are very rarely known as anything different. So, for example, you'll see "two octaves plus a fifth" instead of a 19th.
Determine an interval between two notes  first method
Learn the number of semitones in all of the simple intervals. Then count how many keys on a piano (or frets on a guitar) you have to go from note 1 to note 2.
Example: you want to know the interval between C and E. You count:
C  1, C#  2, D  3, D#  4
Then you look at the musical intervals chart and see that 4 semitones correspond to a major third.
Alternatively, you can go from note 1 to note 2, naming all the intervals instead of counting semitones.
Example: you want to know the interval between F# and B. You go key by key until you get to B. So:
F#  unison, G  minor second, G#  major second, A  minor third, A#  major third, B  perfect fourth
So the interval between F# and B is a perfect fourth.
Determine an interval  second method
(To use this method you need to know how scales work.)
Intervals consists of a number (second, third, fourth) and its quality (minor, major, perfect). To check the interval between two notes:

Identify the number by counting from note 1 to note 2 in whole steps (two semitones). For now, ignore the accidentals. For example, from G# to E, you count:
G  1, A  2, B  3, C  4, D  5, E  6
E is the sixth note, so the interval is a sixth.

Identify the interval quality  first check if the upper note is in the key of the lower note.
For unison, fourth, fifth, octave  if the 2nd note is in the same key as the 1st  we call the interval perfect. If it isn't  we call it diminished (if we have to lower it) or augmented (if we have to raise it).
For second, third, sixth, seventh  if the upper note is in the key of the lower note, we say it's major. If it's higher  augmented, if it's lower  minor.
How to get from F to C  examples

From F to C we count:
F  1, G  2, A  3, B  4, C  5
We finished at 5, so the interval is a fifth. C is in the key of F major, so it's a perfect fifth.

From C to F we count:
C  1, D  2, E  3, F  4
Fourth. F is in the major scale of C, so it's a perfect fourth.

C to F#:
C  1, D  2, E  3, F  4
We know the number  fourth. But we have to go one semitone higher to reach F#. We have to augment it, so the interval will be an augmented fourth.

C to A:
C  1, D  2, E  3, F  4, G  5, A  6
It's a sixth. A is in the key of C major, so the interval quality is major.

C to Ab:
C  1, D  2, E  3, F  4, G  5, A  6
It's a sixth, but we have to go one semitone lower, as Ab is not in the key of C major. Therefore, it will be a minor sixth.
You can practice this way with any notes, and check with the music interval calculator if you got the interval right.