DJ Tool
Key Compatibility Checker
Do two tracks go together?
The tool — try it now
Choose the Camelot keys of two tracks and see immediately whether they're harmonically compatible. With a mini Camelot visualisation and an explanation of why they fit or don't.
What you learn with it
Quickly checking whether two specific tracks can be mixed harmonically. Essential for preparing a playlist.
How to use the tool
Look up the Camelot key of track A in Rekordbox (for example '8A')
Select it in the left dropdown
Do the same for track B in the right dropdown
The result appears immediately: perfect / very compatible / acceptable / avoid
The mini visualisation shows both keys on the wheel (red = track A, blue = track B)
If two tracks do not fit, rekordbox can shift the key — further than most people assume: the semitone buttons move one semitone per click, and the KEY SHIFT pad mode offers values from −12 to +12 semitones. KEY SYNC matches the key of another deck automatically; the track has to have been analysed first. KEY RESET puts it back.
Common mistakes
Reading the display as permission and no longer listening to the transition. Green only means the most common cause of friction is ruled out.
Laying two heavily vocal tracks over one another. Two voices are almost always a problem, whatever the key.
Transposing a long way to rescue a combination. From about three semitones the voice starts to sound artificial.
15–30 minutes
Take the time in one go — hearing and timing develop through repetition, not through reading.
You have it when you can call the verdict on ten pairs from your own playlist before checking — and at least eight of them are right.
Questions about this tool
Does “not compatible” mean I may never play it?
No. It means: if both tracks run melodically at the same time, you will hear friction. There are two ways out, both common — keep the transition short so the melodies barely overlap, or pull one track's melodic layer back with the EQ. The reading is a warning, not a ban.
Why does it bite even though the reading is green?
Usually because of a voice. Vocals often sit in a different key from the instrumental, or carry notes outside it. The analysis reads the overall sound, not the voice — so a combination can be right on paper and still sound off. Then your ear decides, not the number.
Can I just shift a track into the matching key?
In most programs yes, in semitones and without the tempo changing. Two semitones stay unobtrusive; beyond that you hear it in vocals first. ⚠️ On two turntables it cannot be done at all: there, pitch and tempo hang off the same rotation.
When do I check this — beforehand or in the set?
Beforehand. A set leaves no time, and the decision is really made while sorting the playlist anyway. Check and note your twenty favourite transitions once and you play the night without this question — which is the real gain.
Tool tried — what’s next?
“Learning the Camelot rules” is the matching lesson from phase 9: Harmonic Mixing — Key & Scales (8 lessons). The learning path builds on it: step by step, with comprehension checks and progress that is saved.
- —Progress, XP and streak are saved
- —12 phases from your first track to a club set
- —Free — no download, no payment details
The tools stay free to use without an account.
Embed this on your site
You're welcome to put this tool on your own site for free — blog, forum, course page, anywhere. Copy the code and paste it where the tool should appear.
The one condition: keep the credit line below the frame. That line is the part that points back to DJLearn — without it your page has a free tool and we have nothing.
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title="Key Compatibility Checker — free DJ tool by DJLearn"
width="100%" height="320" loading="lazy"
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<p style="font:13px/1.5 system-ui,sans-serif;margin:8px 0">
<a href="https://djlearn.de/en/tools/key-checker?utm_source=embed" target="_blank" rel="noopener">Key Compatibility Checker</a>
— free DJ tool by <a href="https://djlearn.de/en?utm_source=embed" target="_blank" rel="noopener">DJLearn</a>
</p>Where to learn this
Harmonic mixing