The key of a song or other piece of music is its tonal center and is based upon a single note on which the key is based and after which the key is named. Songs can be sung in any key and still sound correct, so choosing a key is often most important for musical groups, which must play in the same key to avoid cacophony. It is also important to note that you do not sing in only one key; you can sing in any key and the same song may be sung in many different keys.
Figuring Out What Key You Sing In
Record yourself singing a given song. It will help if it is a song you are very familiar with.
Replay your recording while sitting next to a piano or small keyboard. Identify the note around which the song centers with a simple keyboard. This will often be the last note of the melody of a song; it may occur frequently and may be repeated at the end of phrases. If you’re not sure, pick a note that you think is the tonal center.
Play this note at the end of each phrase and play the note with the final notes of the song. If it blends in, or harmonizes, it could be the tonal center. If it doesn’t, you’ve likely chosen the wrong note.
Figure out if the key is major or minor. Any key can be one of these two variations. For example, if you’re singing in the key of C, you can be singing in C major or C minor. To determine this, start at the tonal center and count up four half steps. This note will be the third of the key. For example, in the key of C, which is based on the scale C-D-E-F-G-A-B-C, E is the third.
Look for the third of the scale. When you find it, check to see if the third is four half steps away from the tonic (another word for the note that is the tonal center). If the third is usually four half steps away, then you are singing in a major key. If the third is three half steps away, you are singing in a minor key. If both variations exist, look to see which happens more often, as this will most likely help you determine the key correctly.
Use a simple song to figure out which key you've sung in. Many songs switch keys and tonal centers as they progress, and these will be more difficult to figure out. On a keyboard, a half step is moving from one key to the next, including both the black and white keys.