# How many musical keys are there and what are they? **URL:** \ **Category:** Factual Questions\ **Created:** [September 29, 2005, 2:47am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971 "2005-09-29T02:47:20Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![roger\_thornhill](https://avatars.discourse-cdn.com/v4/letter/r/d9b06d/32.png) [@roger\_thornhill](https://boards.straightdope.com/u/roger_thornhill)\ **Post date:** [September 29, 2005, 2:47am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/1 "2005-09-29T02:47:20Z")
I have a funny feeling that there may be different answers to this, depending on the classificatory procedures used, but there we go. Answers, please. ---
**Author:** ![K364](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k364/32/5_2.png) [@K364](https://boards.straightdope.com/u/K364)\ **Post date:** [September 29, 2005, 4:20am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/2 "2005-09-29T04:20:04Z")
In the modern tonal system, there are 12 major keys and 12 minor keys, so the answer is 24. The major keys and their relative minors are: G-flat (same as F#)/ e-flat (same as d#) D-flat / b-flat A-flat / f E-flat / c B-flat / g F / d C / a G / e D / b A / f# E / c# B / g# F# (same as Gb) / d# (same as e-flat) The sequence above is called “The circle of Fifths”. [Wikipedia explanation](http://en.wikipedia.org/wiki/Diatonic_circle_of_fifths) ---
**Author:** ![roger\_thornhill](https://avatars.discourse-cdn.com/v4/letter/r/d9b06d/32.png) [@roger\_thornhill](https://boards.straightdope.com/u/roger_thornhill)\ **Post date:** [September 29, 2005, 4:37am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/3 "2005-09-29T04:37:53Z")
Thank you. I can see that you’re an E-flat major man! ---
**Author:** ![K364](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k364/32/5_2.png) [@K364](https://boards.straightdope.com/u/K364)\ **Post date:** [September 29, 2005, 5:09am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/4 "2005-09-29T05:09:49Z")
> [@roger thornhill](#): > > Thank you. I can see that you’re an E-flat major man! Very astute! ---
**Author:** ![TJdude825](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@TJdude825](https://boards.straightdope.com/u/TJdude825)\ **Post date:** [September 29, 2005, 5:10am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/5 "2005-09-29T05:10:15Z")
B / g# can also be represented as C-flat / a-flat That, and the two mentioned above are the only three keys that can be expressed two ways. For example, although B-flat is the same note as A#, there is no “key of A#.” ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [September 29, 2005, 5:17am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/6 "2005-09-29T05:17:45Z")
For what it’s worth, there are four different types of minor keys (see [here](http://en.wikipedia.org/wiki/Minor_key)), so the number is slightly larger. ---
**Author:** ![Monty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/monty/32/47_2.png) [@Monty](https://boards.straightdope.com/u/Monty)\ **Post date:** [September 29, 2005, 5:39am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/7 "2005-09-29T05:39:53Z")
That’s very interesting and thanks for the responses! (Yes, I know I’m not the OP; however, I’ve also had this question but didn’t know how to frame it.) That’s for the octave system/sequence. What are the keys (and scales, too) for the pentatonic? ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 5:41am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/8 "2005-09-29T05:41:56Z")
> [@ultrafilter](#): > > For what it’s worth, there are four different types of minor keys (see [here](http://en.wikipedia.org/wiki/Minor_key)), so the number is slightly larger. Well, not really. It depends on how you’re counting, but I’d consider all four of those minor scales part of a single minor key. You might be using a harmonic minor for, well, your harmonies, and a melodic (ascending) and natural minor (decending) for your melodies. Your still in the same key, just using different scales depending on your purpose. Otherwise, we can expand our definition to include all the modes. For each tonal center, there are seven classical modes: ionian, dorian, phrygian, lydian, mixolydian, aeolian, and locrian. On top of that, there are altered modes like the dorian flat 2, the lydian augmented, the mixolydian flat 6, etc… However, in classical Western music theory, there are 12 major and 12 minor keys, for a total of 24. ---
**Author:** ![roger\_thornhill](https://avatars.discourse-cdn.com/v4/letter/r/d9b06d/32.png) [@roger\_thornhill](https://boards.straightdope.com/u/roger_thornhill)\ **Post date:** [September 29, 2005, 5:45am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/9 "2005-09-29T05:45:53Z")
> [@Monty](#): > > I’ve also had this question but didn’t know how to frame it. It helps to be pretty unmusical and simple-minded. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 5:45am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/10 "2005-09-29T05:45:55Z")
> [@Monty](#): > > That’s for the octave system/sequence. What are the keys (and scales, too) for the pentatonic? The pentatonics work exactly the same way. For major pentatonic, just remove the fourth and seventh of any major scale. For minor pentatonic, remove the second and sixth of any natural minor scale. Therefore, you have 12 major pentatonics, and 12 minor. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 5:51am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/11 "2005-09-29T05:51:49Z")
> [@TJdude825](#): > > B / g# can also be represented as C-flat / a-flat > That, and the two mentioned above are the only three keys that can be expressed two ways. For example, although B-flat is the same note as A#, there is no “key of A#.” While A-sharp major only exists in theory (so far as I know), A-sharp minor does exist in practice, being the relative minor of C-sharp major (7 sharps). ---
**Author:** ![GorillaMan](https://avatars.discourse-cdn.com/v4/letter/g/50afbb/32.png) [@GorillaMan](https://boards.straightdope.com/u/GorillaMan)\ **Post date:** [September 29, 2005, 6:29am UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/12 "2005-09-29T06:29:45Z")
My simple answer would be fifteen major and fifteen minor. **K364** ’s list matches the circle of fifths, but only takes us as far as key signatures with six sharps or flats. The next ones along are C# major / A# minor, and C flat major / A flat minor. And these keys certainly do get used - I’ve also seen sections of music which find themselves even further around the circle of fifths, using lots of flats & double-flats. While such passages could, in isolation, be written in a more simple manner, if they’re arrived at via other ‘flat keys’, jumping into a whole load of sharps doesn’t necessarily make sense. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 12:47pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/13 "2005-09-29T12:47:48Z")
> [@GorillaMan](#): > > My simple answer would be fifteen major and fifteen minor. > > **K364** ’s list matches the circle of fifths, but only takes us as far as key signatures with six sharps or flats. The next ones along are C# major / A# minor, and C flat major / A flat minor. :smack: Of course that’s right. I was obviously counting enharmonic keys as the same key (like B-flat minor and A sharp minor). But, in practice, you will encounter 0-7 sharps or 0-7 flats (not counting weird key signatures that include both sharps and flats, like in Bartok) for a total of 15 major and minor keys. ---
**Author:** ![Small\_Clanger](https://avatars.discourse-cdn.com/v4/letter/s/9fc348/32.png) [@Small\_Clanger](https://boards.straightdope.com/u/Small_Clanger)\ **Post date:** [September 29, 2005, 1:19pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/14 "2005-09-29T13:19:49Z")
> [@pulykamell](#): > > . . . not counting weird key signatures that include both sharps and flats, like in Bartok How the flipping heck does that work? Must be murder to read. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [September 29, 2005, 1:45pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/15 "2005-09-29T13:45:00Z")
[QUOTE=pulykamell. . .key signatures that include both sharps and flats, like in Bartok. . .[/QUOTE] Never knew this. The _key signature_ contains both? I would think it would be much better to write to a standard key signature then just put the extra accidentals in as needed. You would have to make a career out of reading a sig like that. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 2:48pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/16 "2005-09-29T14:48:53Z")
> [@CookingWithGas](#): > > Never knew this. The _key signature_ contains both? I would think it would be much better to write to a standard key signature then just put the extra accidentals in as needed. You would have to make a career out of reading a sig like that. Yes–there was a beginner’s book of Bartok that I bought for my girlfriend years back which had the key signature of a single sharp (F sharp) and a single flat (B flat). I don’t remember what the tonic was, but if it were C, then that would be the lydian mode with a flatted seventh (dominant lydian, as I call it. You can hear it in the Simpsons theme song). It’s actually quite easy to read. ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [September 29, 2005, 2:52pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/17 "2005-09-29T14:52:06Z")
> [@pulykamell](#): > > Yes–there was a beginner’s book of Bartok that I bought for my girlfriend years back which had the key signature of a single sharp (F sharp) and a single flat (B flat). I don’t remember what the tonic was, but if it were C, then that would be the lydian mode with a flatted seventh (dominant lydian, as I call it. You can hear it in the Simpsons theme song). > > It’s actually quite easy to read. Look at it another way, it’s G melodic minor, but the same descending as ascending. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [September 29, 2005, 2:56pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/18 "2005-09-29T14:56:35Z")
> [@Malacandra](#): > > Look at it another way, it’s G melodic minor, but the same descending as ascending. You could think of it that way, but I find it much easier to think of it as C lydian with a dominant 7th. It all depends on the tonic, as you can think of any mode in terms of any other mode, but I feel it just confuses the issue. If C is the tonic, I think of it in my way. If G is the tonic, I think of it your way. If something else is the tonic, I think of it in terms of that tonal center. The Bartok I’m thinking of is “Microkosmos.” That collection of pieces also has unusual key signatures like a single flat, but the noted flat is A-flat, not the customary B-flat. There’s also one where there’s a single sharp, but it’s the C-sharp, not the F-sharp. ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [September 29, 2005, 3:11pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/19 "2005-09-29T15:11:54Z")
Rings a bell, though if I’ve seen it, it’s not been for the better part of thirty years. Didn’t old Bela write something for piano where the left and right hands had different key signatures? ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [September 29, 2005, 3:16pm UTC](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971/20 "2005-09-29T15:16:57Z")
I’ve heard of a piece like that, but attributed to John Cage. [Next page](https://boards.straightdope.com/t/how-many-musical-keys-are-there-and-what-are-they/323971.md?page=2)