Prelude 1 in C major
BWV 846 · 35 bars · 35 chords
The chords under Bach's Well-Tempered Clavier
Every prelude here has been reduced to its harmony: one block chord per chord change, in the register Bach actually wrote it, with the figuration stripped away. Play the skeleton first and the piece stops being a wall of sixteenth notes — it becomes a chord progression you already know how to hear.
Looking for your level rather than Bach's order? Browse every piece from easiest to hardest, tagged by composer and difficulty.
Why play the harmony first
Sight reading is pattern recognition. The reason a Bach prelude looks hard at first glance is that the pattern is hidden inside the figuration — bar 1 of the C major prelude is five notes repeated in a rocking shape, but what it is is a C major chord. Once you have played the chord, your eye stops decoding sixteen separate noteheads and starts seeing one harmony with a shape drawn through it.
This is old teaching, not a new idea. It is what a teacher does when they sit down and block out the left hand before letting you attempt the piece. The reductions below just do it for all forty-two preludes at once.
How to use these
- Play the reduction, slowly, in time. One chord per bar in most cases. Listen for where the harmony actually moves — it is usually less often than you expect.
- Say the function out loud. Each chord is labelled:
I,V7,V7/V. Naming it is what makes it stick, and it is what lets you predict the next one on a piece you have never seen. - Then open the real score. The figuration will read as decoration over something you already have in your hands, which is the whole point.
How to read the labels
Labels are functional rather than figured bass, because functional is what you can use at speed. V7 is the dominant seventh. V7/V is the dominant of the
dominant — a chord that points at the next one rather than sitting still. A note in brackets is
the bass when it is not the root: V7 (B) is a dominant seventh with B underneath.
Where a chord is labelled viio7/ii, it is a leading-tone chord aimed at the second
degree — the harmonic equivalent of a road sign.
A few bars have no chord label. Those are the ones no triad or seventh explains — a suspension, or a pedal note holding under a change. The reduction says so rather than forcing a name onto them, because a wrong label is worse than an honest gap.
Book I
Prelude 2 in C minor
BWV 847 · 38 bars · 65 chords · harmony moves mid-bar in 27 places
Prelude 3 in C-sharp major
BWV 848 · 104 bars · 104 chords
Prelude 4 in C-sharp minor
BWV 849 · 39 bars · 44 chords · harmony moves mid-bar in 5 places
Prelude 5 in D major
BWV 850 · 35 bars · 60 chords · harmony moves mid-bar in 25 places
Prelude 6 in D minor
BWV 851 · 26 bars · 46 chords · harmony moves mid-bar in 20 places
Prelude 7 in E-flat major
BWV 852 · 70 bars · 202 chords · harmony moves mid-bar in 132 places
Prelude 8 in E-flat minor
BWV 853 · 40 bars · 49 chords · harmony moves mid-bar in 9 places
Prelude 9 in E major
BWV 854 · 24 bars · 36 chords · harmony moves mid-bar in 12 places
Prelude 10 in E minor
BWV 855 · 41 bars · 63 chords · harmony moves mid-bar in 22 places
Prelude 11 in F major
BWV 856 · 18 bars · 41 chords · harmony moves mid-bar in 23 places
Prelude 12 in F minor
BWV 857 · 22 bars · 58 chords · harmony moves mid-bar in 36 places
Prelude 13 in F-sharp major
BWV 858 · 30 bars · 49 chords · harmony moves mid-bar in 19 places
Prelude 14 in F-sharp minor
BWV 859 · 24 bars · 44 chords · harmony moves mid-bar in 20 places
Prelude 15 in G major
BWV 860 · 19 bars · 20 chords · harmony moves mid-bar in 1 places
Prelude 16 in G minor
BWV 861 · 19 bars · 47 chords · harmony moves mid-bar in 28 places
Prelude 17 in A-flat major
BWV 862 · 44 bars · 46 chords · harmony moves mid-bar in 2 places
Prelude 18 in G-sharp minor
BWV 863 · 29 bars · 33 chords · harmony moves mid-bar in 4 places
Prelude 19 in A major
BWV 864 · 24 bars · 42 chords · harmony moves mid-bar in 18 places
Prelude 20 in A minor
BWV 865 · 28 bars · 31 chords · harmony moves mid-bar in 3 places
Prelude 21 in B-flat major
BWV 866 · 20 bars · 33 chords · harmony moves mid-bar in 13 places
Prelude 22 in B-flat minor
BWV 867 · 24 bars · 53 chords · harmony moves mid-bar in 29 places
Prelude 23 in B major
BWV 868 · 19 bars · 61 chords · harmony moves mid-bar in 42 places
Prelude 24 in B minor
BWV 869 · 47 bars · 105 chords · harmony moves mid-bar in 58 places
Book II
Prelude 2 in C minor
BWV 871 · 12 bars · 20 chords · harmony moves mid-bar in 8 places
Prelude 4 in C-sharp minor
BWV 873 · 62 bars · 62 chords
Prelude 5 in D major
BWV 874 · 57 bars · 68 chords · harmony moves mid-bar in 11 places
Prelude 6 in D minor
BWV 875 · 62 bars · 95 chords · harmony moves mid-bar in 33 places
Prelude 7 in E-flat major
BWV 876 · 71 bars · 203 chords · harmony moves mid-bar in 132 places
Prelude 8 in D-sharp minor
BWV 877 · 37 bars · 61 chords · harmony moves mid-bar in 24 places
Prelude 10 in E minor
BWV 879 · 109 bars · 109 chords
Prelude 11 in F major
BWV 880 · 72 bars · 130 chords · harmony moves mid-bar in 58 places
Prelude 12 in F minor
BWV 881 · 71 bars · 104 chords · harmony moves mid-bar in 33 places
Prelude 13 in F-sharp major
BWV 882 · 75 bars · 82 chords · harmony moves mid-bar in 7 places
Prelude 14 in F-sharp minor
BWV 883 · 43 bars · 66 chords · harmony moves mid-bar in 23 places
Prelude 15 in G major
BWV 884 · 49 bars · 67 chords · harmony moves mid-bar in 18 places
Prelude 17 in A-flat major
BWV 886 · 77 bars · 99 chords · harmony moves mid-bar in 22 places
Prelude 18 in G-sharp minor
BWV 887 · 45 bars · 79 chords · harmony moves mid-bar in 34 places
Prelude 20 in A minor
BWV 889 · 33 bars · 105 chords · harmony moves mid-bar in 72 places
Prelude 21 in B-flat major
BWV 890 · 88 bars · 179 chords · harmony moves mid-bar in 91 places
Prelude 23 in B major
BWV 892 · 24 bars · 38 chords · harmony moves mid-bar in 14 places
Prelude 24 in B minor
BWV 893 · 62 bars · 89 chords · harmony moves mid-bar in 27 places
What this is and is not
These are 1,868 bars reduced to 3,023 chords by software, then checked. The harmony is an analysis, not gospel: where two readings are defensible it picks one, and on a handful of bars — suspensions, pedal points, the odd chromatic passing chord — it will pick the duller one. Argue with it. Arguing with a harmonic reading is itself the exercise.
Six preludes from Book II are missing because the digital sources for them could not be read cleanly, and a silently wrong score is worse than an absent one. The rest of Book II is here.
The MusicXML files open in MuseScore, Sibelius or Dorico if you want to transpose them, print them, or drop them into your own practice. They are also importable straight into the trainer.