2.18Flat-key shortcut

For flat major keys:

The second-to-last flat is the name of the major key.

Example:

B♭ E♭ A♭

Second-to-last = E♭

So:

E♭ major

B♭ E♭ A♭ D♭

Second-to-last = A♭

So:

A♭ major

Exception:

One flat = F major.