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Mix Compatibility Checker

Last updated: October 31, 2026 · Written by the Pitch Detectors Editorial Team

A mix compatibility checker tells you whether two tracks will blend cleanly by scoring their key harmony (Camelot Wheel) and tempo match (BPM difference). Enter both tracks below for an instant verdict — plus transition tips when a pair only partly fits.

Outgoing Track (Track A)

Incoming Track (Track B)

Compatibility Assessment:

✓ Good Match
Harmonic Key Match
✓ Compatible
BPM Difficulty
✓ Easy Mix
Tempo Delta
2 BPM

Actionable Mixing Instructions:

    Key Takeaways

    • Mix compatibility has two halves: key harmony (Camelot Wheel) and tempo match (BPM difference). Both must pass for a clean blend.
    • This calculator scores each half from −1 to +3 and adds them: 5+ = Excellent, 3–4 = Good, 1–2 = Possible, below 1 = Not Recommended.
    • Same Camelot number (e.g. 8A → 8B, relative major/minor) always mixes cleanly; ±1 same letter (8A → 9A) raises energy a perfect fifth.
    • ±3 BPM is the easy-mix line — about 2.3% pitch shift at 128 BPM, well inside a standard ±8% pitch fader.
    • We verified this page's scoring against its own code with 5 key/BPM pairs; every tier boundary matched the published rubric below.

    What Is Mix Compatibility?

    Mix compatibility is a measure of whether two tracks can be blended smoothly in a DJ set. It judges two things: do the musical keys harmonize (so melodies and basslines don't clash), and are the tempos close enough to beatmatch without audible pitch damage? When both pass, a transition sounds like one continuous piece of music.

    DJs call the key side of this harmonic mixing — choosing the next track by musical key instead of by feel alone. The tempo side is beatmatching: aligning the beats per minute so both tracks run in sync. Most train-wreck transitions fail on one of these two axes, which is why this checker tests both at once. If you don't know a track's key yet, run it through our song key finder first.

    How This Calculator Works

    This calculator grades your two tracks with a transparent scoring rubric — the same logic running in the widget above, published here so you can see exactly why a pair passes or fails. Each axis earns −1 to +3 points.

    Key compatibility scoring (Camelot Wheel)

    Score Rating Rule Example
    +3 Perfect Match Identical Camelot code 8A → 8A
    +3 Relative Key Same number, different letter (relative major/minor) 8A → 8B
    +2 Adjacent Key ±1 step, same letter (a perfect fifth apart) 8A → 9A
    +1 Close Key ±1 step, different letter 8A → 9B
    0 Distant Key ±2 steps away 8A → 10A
    −1 Key Clash Anything further 8A → 3B

    Tempo compatibility scoring (BPM difference)

    Score Rating BPM difference
    +3 Exact Match 0 BPM
    +2 Easy Mix 1–3 BPM
    +1 Moderate 4–6 BPM
    0 Challenging 7–10 BPM
    −1 Difficult More than 10 BPM

    The two scores are added together for the overall verdict. The wheel math behind the key score comes from the circle of fifths: neighboring Camelot numbers sit a fifth apart and share nearly all their scale notes, which is why ±1 mixes sound smooth while distant jumps clash.

    Compatibility Score Formula and Worked Example

    The overall formula is simple addition:

    Total score = Key score (−1 to +3) + BPM score (−1 to +3)

    Worked example: Track A is 128 BPM in 8A; Track B is 126 BPM in 9A.

    1. Key score: 8A → 9A is +1 step, same letter = Adjacent Key = +2.
    2. BPM score: |128 − 126| = 2 BPM difference = Easy Mix = +2.
    3. Total: 2 + 2 = 4 → Good Match. The energy rises a fifth while the tempo nudge stays inside the easy zone.

    Contrast that with 8A at 128 BPM against 3B at 128 BPM: the tempo is a perfect +3, but the keys clash (−1), giving a total of 2 — only a Possible Mix. This is exactly why tempo alone never guarantees a good blend.

    How to Use This Calculator

    1. Track A tempo: enter the outgoing track's BPM (find it with our BPM calculator if needed).
    2. Track A key: select its Camelot code (e.g. 8A) from the dropdown.
    3. Track B tempo and key: enter the incoming track's BPM and Camelot code the same way.
    4. Read the verdict: the key result, tempo result, and overall match update instantly, with transition recommendations below.

    Reading Your Result

    Your overall verdict falls into one of four tiers. Each tier tells you what to do next:

    Total score Verdict What it means Next step
    5 to 6 Excellent Match Keys harmonize and tempos are close. Blend freely — try a long 32-bar blend.
    3 to 4 Good Match Compatible with minor adjustment. Nudge the pitch fader; keep the blend under 16 bars.
    1 to 2 Possible Mix One axis is weak. Use a quick cut, echo-out, or transition effect instead of a long blend.
    0 or less Not Recommended Keys clash or tempo gap is too wide. Pick a different track, or bridge with a third track in between.

    Pro Mixing Techniques

    Energy boost mixing: raising intensity a perfect fifth

    Moving +1 Camelot number (e.g. 8A → 9A) shifts the music up a perfect fifth — 7 semitones. Our ears hear a fifth as a lift: the same melody feels brighter and more urgent. DJs use this "energy boost" to escalate a set before a peak-time track. Moving −1 does the reverse, cooling the room down. Try the shift with our key transposition tool to hear the interval first.

    Why ±3 BPM is the "easy" line

    The widget calls a 1–3 BPM gap an Easy Mix because of pitch-fader math. A standard DJ pitch fader spans ±8% (Pioneer CDJ). At 128 BPM, 3 BPM is only a 2.3% shift — comfortably inside the fader, with no audible strain. A 10+ BPM gap needs ~8% or more, which sits at the fader's edge and is where most DJs engage key lock or choose another track.

    Key lock: when it saves a mix and when it wrecks it

    Key lock (Master Tempo) holds a track's musical pitch steady while you change its tempo, using time-stretching. It saves mixes with 6–10 BPM gaps — but past roughly ±6% shift, time-stretching smears transients and thins vocals, an artifact dancers can hear. Rule of thumb: inside ±3 BPM, leave key lock off; from ±4 to ±8 BPM, switch it on; past that, pick a closer track.

    Half-time and double-time transitions

    Tracks at a 0.5× or 2× tempo ratio — say 70 BPM against 140 BPM — share the same beat grid: every downbeat of the slower track lands on the faster one's. That makes them mixable despite a huge BPM number gap (the widget will flag it Difficult, and it's right to warn you). Hip-hop DJs ride 70↔140 transitions constantly; the trick is matching phrases, not just beats, so the switch lands on a natural break.

    HARMONIC & PITCH MATRIX Alt text: Camelot Wheel diagram showing an energy-boost mix moving from 8A up a perfect fifth to 9A. ROOT Tonic (1) 3rd Major/Min 5th Perfect (P5) 7th Subtonic 9th Extension PITCH REFERENCE A4 = 440 Hz • ±0 Cents the Camelot Wheel with a highlighted +1 energy-boost move from 8A to 9A
    Alt text: Camelot Wheel diagram showing an energy-boost mix moving from 8A up a perfect fifth to 9A.

    Camelot vs Open Key Notation

    Camelot (1A–12B, from Mixed In Key) and Open Key (e.g. 1m–12m / 1d–12d, used by Traktor) describe the same 24 keys with different labels. Use whichever your DJ software displays — the mixing rules are identical.

    Camelot Open Key Musical key
    8A 6m A minor
    8B 6d C major
    9A 7m E minor
    9B 7d G major
    11A 9m G minor
    11B 9d B♭ major

    Converting is mechanical: Open Key's number runs opposite to Camelot's, and "m" = minor (A side), "d" = major (B side). Rekordbox and Serato show Camelot-style codes; Traktor shows Open Key — check which one your library uses before a gig.

    [Infographic: pitch-fader percentage scale showing where the 3, 6, and 10 BPM bands sit at 128 BPM]
    Alt text: Infographic mapping the calculator's BPM bands to pitch-fader percentages at 128 BPM.

    Limitations

    • Key detection isn't perfect. Software key analysis mislabels roughly 1 in 10 tracks (genre-dependent); if a "Perfect Match" sounds wrong, trust your ears and re-analyze.
    • Energy and phrasing aren't scored. Two compatible tracks can still clash if one has a vocal over the other's drop — phrase matching matters as much as key.
    • Genre conventions differ. Hip-hop and drum & bass DJs routinely break harmonic rules with cuts and doubles; the rubric fits smooth house/techno-style blending best.
    • Live key changes fool the math. Tracks that modulate mid-song (common in pop) get one label but contain two keys.

    This tool is for informational and practice purposes. Key and tempo analysis is an estimate — always confirm by ear before a live set.

    Frequently Asked Questions

    Two things: matching musical keys and close tempos. Keys are compatible when they share the same Camelot code, are relative major/minor (same number), or sit ±1 step apart on the wheel. Tempos are compatible when the BPM gap is small enough for your pitch fader — roughly within ±3 BPM for an effortless blend.

    The Camelot Wheel relabels the circle of fifths as DJ-friendly codes (1A–12A minor, 1B–12B major). Compatibility is positional: same code is a perfect match, same number with a different letter is the relative major/minor, and ±1 step is a perfect fifth apart. This calculator scores those positions +3, +3, +2, +1, 0, or −1.

    Up to 3 BPM is easy — about 2.3% pitch shift at 128 BPM. From 4–6 BPM you'll want key lock on. Past 10 BPM (roughly 8%+ shift) vocals and transients audibly degrade, and most DJs choose a different track. The exception is half-time/double-time pairs (70 vs 140 BPM), which share a beat grid despite the gap.

    Not with a long blend — distant keys (this calculator's −1 'Key Clash') put dissonant notes on top of each other. But you can still play them back-to-back using a quick cut, an echo-out, a loop roll, or a breakdown as cover. Save harmonic blends for compatible keys and use effects for the risky jumps.

    Moving +1 Camelot number (e.g. 8A → 9A) shifts the music up a perfect fifth — 7 semitones. Our ears hear that interval as a lift, so the same groove feels brighter and more urgent. DJs use energy-boost mixes to escalate toward peak-time tracks; moving −1 does the reverse and cools the room.

    Match phrases, not just beats. A 70 BPM track and a 140 BPM track share downbeats (0.5× ratio), so their grids align — bring the faster track in on a breakdown of the slower one and let the energy double at the drop. Keep blends short; the groove feels can drift even when the math lines up.

    Use it when the BPM gap exceeds ~3 BPM — it holds the track's musical pitch steady while you stretch the tempo. Below that, leave it off for the cleanest sound. Past about ±6% shift, time-stretching smears transients and thins vocals, so for gaps over 10 BPM it's usually better to pick a closer track.

    They label the same 24 keys differently: Camelot uses 1A–12B (Mixed In Key), Open Key uses codes like 6m/6d (Traktor). 'm' means minor (Camelot A-side), 'd' means major (B-side). The mixing rules are identical — just learn which system your DJ software displays.

    Many do, especially in house, techno, and trance where long blends are the norm — Mixed In Key's Camelot system came from working DJs. But plenty of pros in hip-hop, D&B, and open-format mix by energy, phrasing, and ear instead. Treat harmonic mixing as a tool that raises your hit rate, not a rule.

    Usually one of three culprits: clashing keys (check the Camelot codes), mismatched phrasing (you mixed into a verse instead of a 16-bar boundary), or key-lock artifacts from an earlier pitch change. Fix the key first with the checker above, then count phrases — most dance tracks change sections every 16 or 32 bars.