Mixed In Key or a set analyzer?

Mixed In Key is desktop software for preparing a music library. It detects the key, tempo and energy of each track, shows the key in Camelot notation, finds cue points, and writes the results into your files as tags so Rekordbox, Serato, Traktor and the rest can read them. Mark Davis of Mixed In Key created the Camelot system, so the notation on this whole site originates there.

MixGrade does none of that. It takes one audio file, a recording of a set you already played, and scores the performance: tempo drift inside each transition, the distance of each key move, bass clash, energy shape, loudness and clipping. It produces a MixScore out of 100 and a report per transition. It does not tag anything and it does not know your library exists.

If the problem is that you do not know the key of the 4,000 files on your drive, buy Mixed In Key. Nothing on an iPhone will tag a library, and MixGrade explicitly will not: it reads a single recording and leaves your files alone.

The same goes for cue points, for energy sorting inside your DJ software, and for planning a set in advance. That is library preparation, it happens on a computer, and it is what Mixed In Key was built for. A per-track key detector also has an easier job than a set analyzer, because it gets a whole clean track to correlate rather than a passage in the middle of a blend.

Knowing that two tracks were compatible tells you nothing about whether your blend between them worked. Preparation software never hears your performance. It cannot know that the tempo slipped 2.4 BPM at 41 minutes, that both basslines ran together for twelve seconds, or that you were clipping into the red at 2:44.

Those are the faults that make an amateur set sound amateur, and they only exist in the recording. If you already prepare your library properly and still cannot work out why the set sounds off, the gap is on the performance side.

MixGrade’s key detection has the harder job and is the weakest of its five measurements. It reads chroma over ten second windows and requires twenty seconds of evidence before it accepts a key change, so brief modulations get smoothed away and percussive passages can read wrong. A dedicated per-track detector working on a clean file will beat it, and that is a fair criticism.

MixGrade is also iPhone only and requires iOS 26. It has no desktop version and no library features, and its tracklist matching depends on the Shazam catalog, which frequently cannot identify edits, bootlegs or pitched tracks.

Preparing music is one job. Reviewing a performance is another. If you have never keyed your library, start there. If your library is already in order and your blends still are not, the recording is where the answer is, and measuring it is cheaper than guessing.