Song Key Finder Find in what key a song was composed with our online music key Analyzer.

What key is this song in? Easily find the key of a song by extracting it from a MP3 (mp3 to key) or any other audio file thanks our Online Song Key Finder. Drop your audio file(s) in the song analyzer below and instantly get the Key in which a song was composed by magic. Detected Song Keys are 70-95% accurate depending on the selected option, and it's even more if we consider that relative keys share the same key signature.
Hit "download" if you want that we inject the Key found into a custom Song Key Mp3tag (MP3 files only).

Note: if you want to find the tempo, use our BPM Finder to count Beats per minutes instead.
Want to play in tune with this song, use our free Android Guitar Tuner.

Click or drop your file(s) here

What is the key of a song?

Almost all songs and compositions have their key, which makes it a very important part of the music. The key of the song is, let's say, a group of tones and chords that are tonally related, or compatible. That group is based on scales – major and minor, and playing it produces a very melodic sound. There are 12 major and 12 minor keys.

Also, a key has a central note – keynote, also known as the tonic note (or the root), which is the most prevalent note in the song (repeats a lot, and most parts usually start and end with it).

Naturally, a tonic chord is played based on a song key, and knowing those are very important for guitar, piano players or any musician.

Can a song have more than one key?

Yes, of course, and it's not that uncommon. Although people tend to play and compose songs in as few keys as possible (changing too many keys can lead to disharmony and chaotic sound), having two or a few different keys is quite normal. Jazz music is a perfect example of songs having different keys. Improv and chaotic jazz songs can have fantastic key changes played by incredibly talented musicians, but some people can’t stand the sound of it.

But most of the popular songs have maybe two keys and change between them occurs two or three times. Listen to some progressive rock songs (Muse, Tool, ...) and you will hear it for sure (if not, you can always use our free music key detector or music key identifier available on this page).

Are there happy and sad keys?

There are happy and sad keys and they are related to the song scale. The major key is considered to be the happy one, while the minor key is the sad one. Of course, this is not always the case. A song can be performed in a minor key but with high bpm (beats per minute) plus some happy lyrics, like Happy by Pharrell Williams. It will be difficult to call that song sad.

But generally, throughout history, major for happy and minor for sad keys have been heavily used. I don't know if this was conditioned by hundreds of years of this style or not, but listening to music in minor keys definitely results in sad, melancholy emotions.

How important is a song's key if I'm going to be a musician or DJ?

The key of a song is one of the most crucial aspects of music. No wonder why classical composers had key names in titles of their compositions (Mozart's Symphony No. 25 in G minor, for example). Although contemporary music is nothing alike classical music and simplicity is emphasized, that still doesn’t mean that you don’t have to know the basics of music theory.

By understanding keys and practicing them, your compositions will be much more fluent, harmonic, and generally better. If you are a musician, your solos, riffs and improvs will have more ‘meaning’ and your playing technique will come easier. If a DJ, it will be way easier to create the perfect playlist just by knowing the keys, this is called harmonic mixing.

Use this song analyzer to find the key of a song and start practicing right now.

Tips to train yourself to recognize a song's key by ear

If you possess a musical instrument, you can play some chords and songs in specific keys. Over time, you will start to recognize the key automatically. You can add more options, like using a microphone and creating audio data that you can listen to later.

In case you don’t own an instrument, there are many useful mobile apps and online sites that work as key finders such as our own above. This kind of a song analyzer will find the key of a song, find the pitch of a song, song scale, or anything you want. Find and analyze any audio like mp3 songs. It’s a great tool to make your hearing perfect.

What is the relationship between BPM and key?

The key and tempo can be related, but not necessarily. For example, many DJs go for minor keys when dropping BPM (beats per minute), and vice-versa. And when you think about it, lower tempo music sounds much better with minor keys than major, It is known that minor keys are called ‘sad’ and major ‘happy’ – lower beats go well with sad music, and higher beats go well with happy music.

But, the tempo is just a speed (rhythm) of a song, while the key is a combination of tones and notes that go well together. These two don't need to go hand-in-hand and there are no rules for this, but somehow everyone prefers the aforementioned correlation.

How common is it for a note to be played outside of a key's signature?

Very common. The world has a fantastic music history with millions of songs and compositions created so far. Many of those have ‘accidentals’ (notes that don’t belong to a specific key signature or scales) and thank God that’s the case. Can you imagine if every song followed strict rules? There would be no improvisation, no creativity! We would have gotten bored with music.

Following a key is important as it provides a standard for a nice melody and avoids chaos. But being naughty from time to time is always a good thing.

Examples of songs that are "off key"

Unfortunately, there are many singers today that cannot hit the key when performing or recording. For singers having trouble in the studio, professionals heavily use auto pitch-correction (like autotune) and manual tuning tools (ie. Melodyne) so they sound pitch -perfect. Real-time autotune is another trick used in live performances, but it can't correct (at least for now) the notes way off key. Some of the singers you can hear perform off key live are Taylor Swift, Ariana Grande, Demi Lovato... just to name a few. Or is it possible that they are trying to implement something new or express themselves in that specific way? We don't know.

Many of the rappers and punk bands have this style, most notably Kanye West, Outkast, even Red Hot Chili Peppers.

Does the first chord define the key of a song?

Well, usually yes. The first and the last notes of the song typically describe the same key. If a song is in C, the first note or chord will probably be C. The last one may or may not be C, for key changes can occur during the song, but when continuing the C scale, the last note will most commonly be C as well. The notes in C key are comprised of C scale, and that will be the most common note in the song.

Can I write a song without a key?

In theory, it is possible to write a song without a key. Key means ‘tonality’, so theoretically you can compose a song without any tonality. Following the key is more or less a guideline, not a must. Creating a song without scales and just mixing notes can be done, but the results are not promising. When composing a song, you need as much help as possible to make it perfect, and using the key and scales is certainly a way of doing so. Some apps can help you with this as well. You can extract beats and notes from some mashups performed by some DJ in a live set, make the noise compatible, and voila you have a song. If you pull this out, you are a great musician.