Content

• To step
• Part 1 of 3: Getting familiar with a few musical concepts
• Part 2 of 3: Reading notes to determine the key
• Part 3 of 3: Finding out the key by ear
• Tips

Being able to determine the key of a song or piece of music is a valuable musical skill. Knowing the key allows you to transpose (change the key) the music to better suit your voice. It gives you the opportunity to experiment with giving a song a different sound (a great skill in creating an interesting cover of a song). In order to determine the key of a song or piece of music, you will need to have some basic knowledge of music theory. A piano is the best tool to use in providing examples for understanding and explaining these concepts.

To step

Part 1 of 3: Getting familiar with a few musical concepts

1. Understand whole and half tone gaps. Half distances and whole pitch distances are both intervals, or the distance between two notes. These are the building blocks of scales.
   • A scale is a group of notes in ascending order. They are spread over one octave, a series of eight notes (derived from the Latin word octavus or eight). For example, the major scale in C goes like this C D E F G A B C. The bottom note of a scale is called the "tonic" or root note.
   • If you think of the above scale as an actual ladder, each half-pitch is one step above the previous one. So the distance between B and C is half tone distance because there are no other steps in between. (On a piano, the B and C are the white keys that are directly next to each other, without a black key in between.) However, the distance from C to D is quite a tonal distance, because there is an extra step between those notes on the ladder (eg the black key on the piano between the C and D key is a C # or a Db).
   • In the C major scale, the only semitone distances are those between B and C and between E and F. All other intervals are whole distances, because the C major scale does not contain a sharp (#) or flat (♭).
2. Understand the major scale. The major scale always follows the same pattern of whole steps (1) and half steps (½): 1 - 1 - ½ - 1 - 1 - 1 - ½. So the C major scale is the sequence C D E F G A B C.
   • You can create any other major scale by changing the starting note - the root - and following the same interval sequence.
3. Understand minor scales. Minor scales are a bit more complex than major scales and can follow various patterns. The most commonly used sequence of notes for minor scales is the natural minor scale.
   • The natural minor scale has a pattern of whole and half tone intervals that runs as follows: 1 - ½ - 1 - 1 - ½ - 1 - 1.
   • You can transpose (convert to a different pitch) this scale sequence by starting on a different note and working your way up from the root note at the same intervals.
4. Understand the third and fifth. Thirds and fifths are certain intervals (distances between notes) that are very common in music. They are useful for determining the key of the music. Minor intervals are half pitch less than major intervals, changing their sound.
   • A third is formed by the interval between the first note in the scale and the third note. A major third has two whole steps between notes, while a minor third has three half steps.
   • A fifth is made by the first note of the scale and the fifth note. A "perfect" fifth has seven semitone intervals.
   • In Leonard Cohen's song 'Hallelujah' is sung about the intervals, in the following line: 'It goes like this, the fourth, the fifth, the minor fall, the major lift, the baffled king composing' Hallelujah '.' In Much pop music (often written in C major), is a particularly prominent chord progression moving from the "fourth" to the "fifth" which is a "cheerful" sounding movement. In the song, the words "minor fall" are accompanied by a minor chord, and the words "major lift" by a major chord.
5. Understand major chords. A standard chord is made up of three notes, one triad, which are arranged in thirds (see Step 4). These chords are usually based on a scale, such as the C major. Major chords have two whole pitches between the first and second notes of the triad. A major chord contains a major third (third) and a perfect fifth (fifth). The first note of a chord is called the root note of the agreement.
   • For example, to make a chord based on a C major scale, you can start in C, the "tonic", and use it as the "root" of your chord. Then move on to the third / third of that scale (4 semitones upwards) to the E, and then to the fifth / fifth of that scale (3 semitones further up to the G). So the major chord's triad is C - E - G.
6. Understand minor chords. The sound of most chords is determined by the third note, third, or middle note in the triad. Minor chords have three semitones between the first and second notes of the triad, as opposed to the four semitones (or two whole steps) of major chords. A minor chord contains a minor third and a perfect fifth.
   • For example, if you play your fingers one key higher from the root of the C major chord, you will play this chord: D - F - A. This chord is called a D minor chord because the interval between the first and second notes of the chord (D and F) is 3 half-tone steps.
7. Understand diminished and augmented chords. These chords are less common than the major and minor chords, but are sometimes used to create certain effects. Due to the change of familiar triads, they create a melancholic, ominous or even ghostly feeling in the music.
   • The A diminished chord contains a minor third and a diminished fifth (a fifth that is lowered by half a pitch). For example, a diminished C chord is structured like this: C - E ♭ - G ♭.
   • An augmented chord contains a major third and an augmented fifth (a fifth raised by half a pitch). For example, an excessive C chord would look like: C - E - G #.

Part 2 of 3: Reading notes to determine the key

1. Look for the accidentals. If you have printed sheet music, you can recognize the key to a song by going to the accidentals to watch. These are the marks between the accidentals (either the treble clef or the bass clef) and the measure (the numbers that look like a fraction).
   • Here you see either a sharp # (for the raised notes) or a flat ♭ (for the decreased notes)
   • If you don't see # or ♭, the number is in C major or A minor.
2. Read the moles. For accidentals with flats, the key is the second to last flat (the second from the right) seen from left to right.
   • For a track with flats B ♭, E ♭, and A ♭, E ♭ is the second-to-last flat, so the track is in the key of E flat.
   • If there is only one flat, the number is in D minor or F major.
3. Read the crosses. For accidentals with sharps, the key of the note is half a pitch up from the last sharp.
   • When a number has the sharps F # and C #, the next note is up from the C #, the D, and so the piece is in D.
4. Look at the chord diagram. If you play guitar, you probably prefer to use chord diagrams when you want to learn to play new music. Many songs start and end with the chord that matches the accidentals. If a piece of music ends with a D chord, it is probably in the key of D.
   • The three basic chords in the key of C major are C major (C - E - G), F major (F - A - C), and G major (G - B - D). These three chords form the basis of many pop songs.
5. Learn a few scales. By learning some of the more common scales within the type of music you play, you can find out what key a song is in. The notes in your chord all fit the scale.
   • For example, the F major chord is F - A - C, and each of these notes belongs to the C major scale, so the F major chord belongs in the key of C.
   • The A major chord (A - C # - E) is seated not in the key of C, because the C major scale has no sharps.
6. Try to guess. Most popular music uses only a few commonly used keys, as they are the easiest to play on the guitar or piano (often used as accompaniment).
   • C is by far the most common key for pop songs.
   • Look in the music for the following notes that make up the C major scale: C - D - E - F - G - A - B - C. Do the notes of the music match the notes in the scale? If the answer is "Yes," then the number is probably in C.
7. Note the omens in the music. Keep in mind that music sometimes includes accidentals, the notes with a ♭, #, or a fix, even though such accidentals don't indicate that that note always has a ♭, #, or a fix.
   • Accidental signs in the music do not change the key of the track.

Part 3 of 3: Finding out the key by ear

1. Determine the tonic. The tonic, or the first note of the scale, sounds good just about anywhere in the song. Using a piano or your own voice, play one note at a time until you hit a note that "feels" just right for the song.
2. Test the tonic. By playing other notes in the triad, you can hear if the chord seems to fit in the song. Play the fifth above the note you think is in the tonic. The fifth should also sound as if it would fit most of the song, as it is the second most stable note in a scale.
   • Play the note half a pitch below the tonic, also known as the seventh note or the seventh. There is tension in the context of the song, as if this note would like to dissolve in the tonic.
3. Determine whether the number is in major or minor. Play the note up a major third from the tonic. If this note fits within the song, chances are it is in a major key. If not, play a minor third (3 ♭) and hear if it fits better.
   • Try to tell the difference between a major and a minor chord by playing the following triad: C - E - G is a major chord with C as the tonic. Now change the E to E ♭. C - E ♭ - G. Listen for the difference in feel and tone.
   • You may be able to guess whether it is a major or a minor simply by how the song feels, because in Western music, songs in a minor key appear sad or thoughtful.
4. Try a few chords. The most commonly used chords of a scale should also appear in the strings of the music track. A common scale is the G major scale, which follows the pattern of a major scale: G - A - B - C - D - E - F # - G. Its chords are G major, A minor, B minor, C major, D major, E minor, and F # diminished.
   • Songs in the key of G major will have chords corresponding to these notes.
   • For example, the Green Day song, "(Good Riddance) Time of Your Life" begins with a G major chord (G - B - D), followed by a C major chord (C - E - G). These chords are both in the G major scale, so the song is in the key of G major.
5. Sing along with the music. Pay attention to the songs that you find easy to sing along versus songs that feel uncomfortable because they are too high or too low. Note the keys of songs that are easy to sing and songs that are difficult to sing.
   • Over time, you will realize that some keys easily fall within that range, while other keys may make it more difficult for you to hit all the notes. This allows you to make a reasonable estimate of the key before you even start choosing an instrument.
6. Practice your new skill. Create a playlist of some of your favorite songs to sing along, or use the radio to try what key the song is in. You may be starting to discern patterns. Songs that are in the same key can then be recognized.
   • Keep a list of the songs you have studied and sort them by key.
   • Listen to different songs in the same key one after the other to get a feel for that key.
   • Listen to the contrast between songs in different keys to see if your hearing can pick up the difference.
7. Check your findings. Understanding the basics of music theory is an excellent idea when you want to write your own songs or adapt the songs of others to suit your own style, but sometimes you just need a quick key check. There are a number of apps for your mobile and websites that can help you determine the key of a song.
   • A search for the name of a song and the key can quickly give you an answer.
   • When you start learning how to recognize a key by ear, it is a good idea to check that your answer is correct.

Tips

• This article contains many confusing terms from music theory, but once you start practicing scales and chords on a real instrument, it will become much clearer.
• Listen to a song that you know the key of, and try to cut out the chords in that song. The more you practice and refine your "ear", the easier it will become to identify the key of the song.