Every list of the chords a jazz beginner should learn first is an opinion. Some of them are very good opinions, but you cannot check them, and the lists disagree with each other in ways nobody ever explains.
So here is a count instead. The app ships a Gig Book of 1,748 standards, and every chart in it is stored as a sequence of chord symbols. We parsed all of them, threw away the roots, and tallied what was left: the chord quality, which is the part that says major seventh or minor seventh or diminished, and the part you actually have to learn. That is 62,532 chord symbols naming fifty-nine distinct chords.
Chords, not spellings. A chart writes a half-diminished chord three different ways and a major seventh two, so the tally folds the spellings together first, using the app’s own map from written symbol to actual notes. Counting the raw shorthand instead splits one chord across three rows, which is not a small distortion: it is the difference between the half-diminished chord sitting sixth on this list and appearing to be tied for seventh.
Every number on this page is recomputed from those charts on each build, and each one is bound to the sentence that states it. If the prose and the measurement disagree, the page does not deploy.
Here is what came back.
What the count says
Three chords carry most of the writing. Dominant seventh, minor seventh and major seventh together are 64.6% of every chord symbol in this corpus, and the first two alone are 52.7% between them. Learn those three in all twelve keys, one voicing each, and across the whole book roughly two chord symbols in every three are ones you already have an answer for.
Across the whole book, though, and not on any particular page. That share swings enormously from tune to tune — some standards are almost nothing else, and some will hand you four unfamiliar chords in the first eight bars. Being stopped is the entire beginning of jazz piano, and an average cannot tell you when.
Ten take you to 87%. That is the number this post is named after, and it is the reason the usual advice is not wrong so much as badly ordered: there is no point drilling altered dominants in twelve keys while you are still counting on your fingers for a plain minor seventh.
The remaining forty-nine share what is left. Rarity is not unimportance — a 7♯11 is unforgettable when it arrives, and a tune that needs one needs it — but a chord you will meet a handful of times is not where the first hundred hours go.
The top three are one hand shape
There is a reason the first three rows are worth learning together rather than one at a time, and it is not just that they form a ii-V-I.
Play the root, the third and the seventh of a major seventh chord and leave everything else out. In C that is C, E and B. Now lower the B by a semitone: C, E and B flat, which is a dominant seventh. Now lower the E by a semitone as well: C, E flat and B flat, a minor seventh.
The three commonest chord symbols in this corpus are the same three fingers, with two notes moving by a semitone each. That is the whole of it, and it is why this stripped-down shape is the first voicing most players learn: it carries the minimum that tells those three apart, which is whether the third is major or minor and whether the seventh is major or flat.
Be precise about what it is doing, though, because it is easy to overclaim. Even for those three it identifies the quality rather than spelling the chord: the fifth is left out, and that is the point — across major seventh, dominant seventh and minor seventh, the fifth is the one chord tone that tells you nothing about which of the three you are playing.
Which is exactly why it stops working further down the table. Seven of the ten rows need a note this shape has nowhere to put. The sixth chords and the plain triads have no seventh at all. A half-diminished chord is defined by its flattened fifth, and a shell of root, flat third and flat seventh is indistinguishable from a plain minor seventh. A diminished seventh needs both a flattened fifth and a double-flattened seventh, so a three-finger shell does not reduce it so much as lose it. And a flat ninth simply vanishes, leaving an ordinary dominant behind. Those are instructions, not colour.
What the shell does is get you through the three commonest chords in the book with a single hand shape, which is a very good trade at the beginning — and it does not stop being useful later. It stays professional vocabulary for solo playing, for sparse accompaniment and for anything where you want the voice leading to be audible. Rootless voicings are the next thing you learn, not the thing that replaces it.
Learn one shape, move two fingers, and you have a usable answer for 64.6% of the chord symbols in this book.
Two things in the table that surprise people
The major sixth chord is the fourth commonest thing in the book. Not an extension, not a colour, not an antique: a chord that occurs more often than a dominant seventh with a flat ninth. If you learned that a tonic chord is a major seventh you have half the picture. The other half shows up whenever the melody lands on the root of the chord: the major seventh is then a semitone below the melody note, which is a hard interval to place. Voiced closely it is a minor second at the very top of the chord; move that seventh down an octave, as drop 2 does, and the same clash becomes a minor ninth between the outer voices. A sixth chord has no seventh in it to collide, which is why arrangers reach for one on a tonic with the root in the lead, and why the block-chord tradition is built on sixth chords rather than major sevenths.
Plain triads are nearly as common as half-diminished chords. The half-diminished chord is 4% of all symbols and a bare major triad is 3.8%, 127 symbols behind it. Jazz pedagogy tends to say triads get replaced by seventh chords, and as a description of what a pianist plays that is fair. As a description of what is written on the chart it is not.
It is worth saying that this row moved. Counting raw chart shorthand rather than chords put the triad sixth and the half-diminished seventh, three symbols apart, and an earlier version of this post called that a tie. It was not a tie; it was one chord written three ways.
What the count is not
Four limits, stated plainly, because a number without its limits is worse than no number.
It counts the main symbol, not the alternates. Charts often print a substitute reading in parentheses above a bar; a player uses it instead of the written chord, not as well as it, so counting both would count one musical moment twice. There are 923 of those in the corpus, and they are excluded on purpose. It is not a small decision, which is why the number is printed here rather than left in a footnote.
It counts symbols, not time. A chord written once and held for four bars counts the same as a chord that lasts two beats. A modal tune that sits on one minor chord for sixteen bars contributes one minor seventh to the total. That makes this a good guide to how often you will meet a chord and a poor guide to how much of the music that chord is.
It counts what is written, not what is played. A chart that says C7 leaves the pianist to decide whether to colour or alter it, and how; sometimes the answer is a raised ninth and sometimes, on a blues tonic or a long Mixolydian vamp, the answer is to leave it exactly as written. The count has no idea which. So the dominant-seventh row is really “the places where you will have to make that decision”, which is arguably more useful anyway.
And it counts this repertoire. Standards, jazz and pop, as they are played on gigs. A corpus of only modal tunes, or only blues, or only Brazilian repertoire would produce a different top ten, and the differences would be interesting. This one is the common ground.
The order to learn them in
The frequency order is not the learning order, and treating it as one would have you drilling major sixth chords before you can play a ii-V-I.
Start with three: minor seventh, dominant seventh, major seventh. They are the top three rows of the table below, and they are also the three chords of a major ii-V-I, which is the progression most of the repertoire is assembled from. Learning them together means every hour of practice is spent on a real progression rather than on isolated shapes.
Add two for the minor key: half-diminished and diminished seventh. They sit at rows six and nine, and they arrive together because the minor ii-V is built from the first of them. The diminished seventh is a bonus with a very high return: there are only three distinct diminished seventh chords in all twelve keys, so learning one shape teaches you four chords at once.
Then the sixth chords, major and minor. Rows four and ten. In a great deal of jazz these are the chords a phrase settles onto, and they are worth having under the hand for that reason. What actually makes an ending sound finished is the cadence around them — where the bass goes, how the voices lead, what the rhythm does — and a major seventh or a plain triad can close a tune just as convincingly. The sixth chord is a colour you want available at the moment of arrival, not a full stop in itself.
Then the dominant with a flat ninth. Row five, and the first genuine alteration on the list. Everything past it is a variation on a chord you can already play.
Leave the plain triads until last, not because they are unimportant but because they are the ones you can already play and the ones a chart will not punish you for simplifying.
That is seven chords before you touch anything that could be called advanced, and between them they cover most of what you will read. The rest are a lifetime’s work, and none of them is urgent.
One caution about the whole exercise
A count tells you what is common. It does not tell you what is worth playing, and the two are not the same. Thelonious Monk’s harmony is barely represented in a tally like this, because what makes it his is not the chord quality written above the staff but which notes he chose inside it and which he left out.
So use this the way you would use a frequency list for a language you are learning. It tells you where to spend the first hundred hours. It has nothing at all to say about what you will eventually want to say.
| # | Symbol | What it is | Times it occurs | Share |
|---|---|---|---|---|
| 1 | 7 | Dominant seventh | 17,413 | 27.8% |
| 2 | m7 | Minor seventh | 15,513 | 24.8% |
| 3 | maj7 | Major seventh | 7,450 | 11.9% |
| 4 | 6 | Major sixth | 2,967 | 4.7% |
| 5 | 7♭9 | Dominant seventh with a flat ninth | 2,568 | 4.1% |
| 6 | m7♭5 | Half-diminished | 2,522 | 4% |
| 7 | (triad) | Plain major triad | 2,395 | 3.8% |
| 8 | m | Plain minor triad | 1,461 | 2.3% |
| 9 | °7 | Diminished seventh | 1,208 | 1.9% |
| 10 | m6 | Minor sixth | 902 | 1.4% |
Questions people actually ask
- Do I really only need ten chords to play jazz?
- Not quite, and it is worth being exact about what the count does and does not say. It says ten chords are 87% of the chord symbols written in this corpus. It does not say you can play a tune with ten chords: a standard that needs an eleventh still needs it, and a chord you meet once in a bridge can stop you as completely as one you meet in every bar. What ten chords buys you is that most of what you read will be familiar, which is a different and more useful promise. And each of them has several voicings; choosing one that suits the melody, the register and the moment is a large part of jazz harmony, and harmony is only one of the things a pianist is doing at once.
- Why is the plain major triad on the list at all?
- Because it is genuinely there in the charts, at 3.8% of all symbols. Beginners are usually told that jazz replaces triads with seventh chords, and as a description of what pianists play that is roughly right. As a description of what is written on the page it is not — plenty of tunes, especially older ones and anything touching Latin or pop repertoire, simply say C.
- Does this count how long each chord lasts?
- No, and that is the most important limit of it. Every chord symbol counts once whether it occupies four bars or two beats, so a tune that sits on one minor chord for a whole section contributes a single minor seventh to the total. The count answers "how often will you meet this chord", which is the right question for deciding what to learn first, and not "how much of the music is this chord", which would need a different measurement.