“In the key of...” — you must have heard this phrase on many occasions in reference to music pieces. Most music, from classical compositions to contemporary pop music, is written, played, and sung in a specific key. Minuets in the key of G minor, rock ballads in the key of E major, jazz pieces in the key of A-flat major, pop songs in the key of C-sharp minor, and so on. But what exactly do we mean when we talk about the key and why does it matter?

Learning about the key is beneficial for all musicians and musical practices, not limited to instrumentalists and classical performances. If you’re a DJ, producer, or somebody who picks an instrument occasionally to jam with your friends, you can significantly improve your improvisation and writing skills, mix songs harmonically, and get a better overall sound by understanding and considering the key.

What is a Key in Music?

The key that a music piece is written in is the identifier of the “main note” (also called the “center of gravity”, “home note”, “tonal center”) that determines the notes and chords sounding most harmonically consonant within that piece of music. The “main note” is the one that a music piece/section normally starts at, revolves around, and finishes on.

Below you can check out the way to find the key of a song by ear and by using online services.

How to Find the Key of a Song Online

There are several services you can use for the task, such as TuneBat, AudioKeychain, and GetSongKey. All of them are similar in function but the latter is used in the following instruction since it supports a wider range of formats and allows to upload files of bigger size in comparison to other online key finders.

1. Open GetSongKey in your browser.
2. Enter the name of the song into the search bar.
3. Wait a few seconds until the results are loaded.
4. Select the suitable option from the drop-down list.
5. Get the information about the key and pitch, open key notation, compatible keys, modulations for musicians, and harmonic mixing info for the DJs, on the page.

In case the song of your interest is not available in the database, follow these steps:

1. Open the key finder page of GetSongKey.
2. Select the key determination accuracy level within the Mode section.
3. Drag and drop the song file onto the upload section.
4. Wait until the process is complete and see the key of the song.

How to Determine the Key of a Song by Ear

1.Listen carefully to the song and focus on the main note. Make sure there are no distractions, it’s best to listen to the song in headphones rather than via speakers. Pay close attention to the music. As you listen to the recording, try to spot the note the music returns to several times throughout the song. The music is highly likely to end on this same note as well. The note will determine what key the song is in.

2. Replay the song and hum the note along as you listen. If you’ve pinpointed the note correctly, it will fit into the background of the song seamlessly. Try to repeat the music behind verses as you hum, it may be more indicative of the actual song key rather than the melody of the bridge or chorus.

3. Play the note on an instrument to validate your choice. Firstly make sure your instrument is in tune; if it’s not, make the necessary adjustments. After that, turn the song on and play the note on your instrument. If it sounds like the note fits along with the song, you’ve correctly identified the main note (and the key).

Note (pun intended) that it may take you several tries before finding the match, especially if you don’t have absolute pitch yet. Don’t give up and try again, treat it as an exercise that is going to help you train your ear to quickly find notes in the future!

4. Consider the mood of the music to find the tonality. Music is commonly written in a major key but you can always indicate the actual tone by focusing on the song mood. If it’s cheerful and upbeat, it’s definitely in the major key. On the other hand, sad, doomy, and menacing sound points to the minor key.

Make sure to only consider the mood of actual music and not the lyrics, though. There are many songs that sound bright but convey a dark message, such as “Hey ya!” by Outkast or “Tears In Heaven” by Eric Clapton.

LALAL.AI, the music source separation service, can help you quickly pull focus only on the instrumental parts of any song. Upload your audio file and the service will isolate the accompaniment stem in a matter of seconds, leaving out the vocal parts altogether.