Mixing In Key for DJs

Mixing In Key

Mixing In Key for DJs

Harmonic mixing with Rekordbox, Serato DJ, Traktor, XDJ-RX2/3, CDJs and XDJs

The easiest way to create a smooth mix that blends seamlessly is to mix in key. Understanding a bit of music theory is necessary to take full advantage of this skill. However, recent DJ software and hardware updates are making it easier than ever to do this without needing a musical background. Let’s get stuck in!

What is a music key?

Two crucial terms are used when talking about the key of a piece of music. These terms often get confused, so it is helpful to establish what they are before moving on. Don’t worry if this seems complicated, whilst some basic music theory is useful to understand music keys, thanks to modern software it is no longer needed to mix in key.

The two terms that really help with understanding mixing in key are:

1) Key: A collection of notes that group together to create a major or minor scale.

2) Scale: The notes belonging to a key in ascending and descending order by pitch, starting and ending on the root note of the key.

For example, if you know that your current track is in C major, we can look at that key’s scale and find that the note G is a part of it. 

(C D E F G A B C)

With this information, we know that a song recorded in G will harmonically mix into our song as G is part of C major’s scale. However, the note F# is not part of the C major scale so we know that a song recorded in the key of F# will not mix harmonically with our song.

If this seems complex, don’t worry, DJs are not expected to know all this. There are various ways to detect the key of a song, and show which other songs will mix harmonically with it.

Ways to show the key of a track

Circle Of Fifths

The fantastic thing about musical keys is that they follow a predictable harmonic pattern. The starting note will always have a progression of notes that naturally follows, thanks to the scale system.

This pattern within the scale also fits into the key correctly, meaning that we can map out the keys to know which key will sound best when mixed into another. This style of mixing is called Harmonic Mixing.

The circle of fifths shows the relationship between the 12 tones in the chromatic scale, their corresponding key signatures, and the associated major and minor keys, all in one handy wheel-shaped diagram.

Circle of Fifths

The Camelot Wheel

The Camelot Wheel is a fantastic way to not only visualise keys, but also to see what other keys would mix in well. It gives each key a number and letter tag, such as 9A, rather than using the traditional naming scheme of Em or Eminor, and gives it a colour.

Keys are denoted by numbers and an A or B to indicate minor or major keys respectively, so E major becomes 12B and D flat minor becomes 12A. It’s easy to see by glancing at the Camelot Wheel that a song recorded in F (7B) would mix harmonically into a song recorded in D minor (7A).

Camelot Wheel

Open Key Notation

The Camelot Wheel is a copyrighted system created by Mixed In Key. A very similar system is the Open Key Notation which is an open-source method of visualising keys and is used in Traktor. Open Key Notation is very similar to the original circle of fifths. The only difference is that Open Key uses D or M to indicate major or minor based on German (dur or  moll) rather than English (major or minor). So F major becomes 12d, and D minor becomes 12m.

Open Key Notation

Finding the key of a track

Finding the key of a piece of music used to involve a thorough knowledge of the above music theory and an excellent ear to find the key manually. However, these days we have various pieces of software that can analyse our tracks and find the key for us. The software is usually very accurate and can even find other information such as the BPM of a track at the same time.

Mixed In Key

The software that started it all! Mixed In Key is an extremely accurate piece of software whose creators developed the Camelot Wheel. Backed by many professional DJs, Mixed In Key analyses your track and then asks you where you want the track’s data to be stored. You can have it written into various places within the track’s metadata, including the track comments, track title or key sections

Because this is a standalone application, it works with most other software. The option to write the key to a track title is ideal for USB DJs working with older CDJs that don’t display key information. There is a handy guide in the software on how to get the key to show in other software should you want this.

Mixed In Key

A view of the options available within Mixed In Key

Serato DJ

The software can now detect the key when analysing songs within the library and is essential to use the Pitch Play features included in the Pitch ‘n Time extension. Even without the Pitch ‘n Time expansion pack, Serato DJ gives users the ability to analyse Key data and display it in various ways within their library.

Serato Key Analysis

Make sure you tick the Set Key box in the Analysis Settings in Serato

Unlike other software in this list, Serato DJ gives you the ability to display the key in a system that suits you best. This includes Camelot (Mixed In Key style), Classical (Musical Annotation), Open Key Notation (as used by Traktor) or Original Tag (which ever way the key is written in the ID3 data).

You can set your preference within the Library View – Preferences in Serato DJ’s settings. There’s an option to secondarily organise your library by key which we find extremely useful. For example, you may have your library organised by BPM but by Holding CTRL (CMD on macOS) on your keyboard and clicking on the Key column it will now organise the keys into harmonic order!

Serato Library Organised By BPM and Key

Serato Library Organised By Key


Pioneer DJ’s rekordbox can both analyse and display key information within a track. However, rekordbox only displays the Key information in Classic form. This is fine if you can remember the circle of fifths but it’s not as easy to work with as Serato DJ or Traktor’s implementation.

With this in mind, a lot of rekordbox users can use Mixed In Key  to write the Camelot Tag info to either a track’s Title or Comments. To find songs within the harmonic range of the selected track in rekordbox you can use the Related Tracks tab to the left-hand side and then select Key. You will then be able to see all the tracks in your library that would harmonically mix well.

Rekordbox Related Tracks

Rekordbox’s related tracks section can help find tracks with the same Key

Pioneer DJ CDJ/XDJ Multi-Players

For the following to work, ensure the songs in your rekordbox library are analysed with Key Information before exporting them to your USB. The two players will also need to be linked. When scrolling through a playlist in the Browse section, any song that will harmonically mix shows with a green key icon next to the BPM. Please note that this icon indicates tracks that are harmonically compatible with the MASTER deck.

An XDJ player showing harmonically compatible tracks

An XDJ player showing harmonically compatible tracks

Alternatively, you can search your library by key. In this view, you can scroll to the key of a playing song highlighted in green. Once you select this, harmonically compatible keys will display and you can press enter on any of these to view the list of compatible tracks inside.


Native Instruments have chosen to use the Open Key Notation system in Traktor. This is very similar to the Camelot Wheel and is quite easy to follow. Unfortunately, unlike with Serato DJ, Traktor doesn’t show the colour of the wheel. However, there is a handy shortcut in Traktor’s library that allows you to view all songs within harmonic range.

Press the magnifying glass icon next to the key on any track in the library view to instantly see all harmonically compatible songs in your library. It’s a quick and easy way to navigate through your compatible tracks without having to change views or settings.

Traktor Key View

Press the magnifying glass next to the Key to view all compatible tracks within your library

In Conclusion

Now that you know how to find the key of your music files, and how to display it in your software, it’s time to start mixing in key. 

Should you mix in key all the time? It’s a much-discussed topic, but, in short, it’s up to you. If you are mixing two tracks with melodies overlapping, then you should always try to mix in key as they will blend much better.

However, if your mix will be completed over a drum loop, for example, there isn’t much benefit to mixing in key as melodic elements aren’t to be found in simple drum loops, but in synths and vocals. When planning a mix, we recommend you take into account the keys of your tracks, but that’s not to say you shouldn’t mix two songs that aren’t compatible. After all, DJing is about being creative and pushing the boundaries of what ‘should’ be done!

Mixing in key is just another tool to make your DJing sound better and isn’t a strict rule you must abide by! Have a go for yourselves and see what tracks harmonically mix with one another. You’ll be surprised to hear how good some of them sound!

This mixing style is most famously used with house music as the genre lends itself to long blends. Blends are taken to another level when the tracks are harmonically matched! In our guide, 3 Ways To Mix House Music, we explore the long blend amongst other crucial house music mixing techniques.

Video Tutorial

Do you want to learn more advanced DJ skills?

Now that you understand keys, take a look at our more advanced DJ courses!

For access to unlimited DJ tutorials and our industry-certified DJ courses, our Complete DJ Package is all you need in your journey to success as a DJ!

Get exclusive industry insights, tips and tricks. Jump onto any Crossfader DJ course you like with lifetime access to all of them! Master an artist mix breakdown or two and send us your mixes to get our professional feedback!

Complete Package members get the best of Crossfader, totally subscription free! Click the link to learn more and take your DJing to the next level with us, or your money back!


Join The Discussion



  1. What Chords Are In Key Of E? – Fallsgardencafe - […] Keys are denoted by numbers and A/B for minor/major keys respectively, so E major is 12B and D-flat minor…

Submit a Comment

Your email address will not be published. Required fields are marked *


Recent DJ Content

Get Involved

DJ Education & Community

Online DJ Courses

Learn how to DJ with your equipment by following our software and hardware specific courses! From Rekordbox to Traktor, Serato DJ to Denon DJ & more!

The DJ Hub

The DJ Hub features advanced techniques, career advice, DJ challenges & an inclusive community. Learn anywhere, any time.