Key & Meter Changes

The header sets the song's starting key and time signature. When the music moves to a new key or meter partway through, you mark the change right where it happens on a chord line — the same tokens you used in the header, dropped inline.

Changing key

Put a key token — the same #Key from the header — on the chord line at the point the key changes:

kf
4/4 #C

VS 8
1  4  5  1   #G   1  4  5  1

A key change mid-chart (to G at bar 3), engraved:

1 1 5 1 5

From #G onward the chart is in G, so the 1 4 5 after it are G–C–D, not C–F–G. The token isn't a chord; it just moves the key — and the key signature — from that spot on. It works in a letter-name chart too: the change still updates the key signature, even though letter chords don't lean on the key.

A whole section can also start in a new key by putting the token on its header (BR 8 #Ab) — see Sections.

Changing time signature

A meter change is written with a T in front of the new signature:

kf
VS
G  D/F#  Em  C   T6/8 Am   T4/4   G  D

T6/8 switches to 6/8 from that point; T4/4 switches back. A change holds until the next T.

The T is required. A bare 6/8 on a chord line would read as a chord — a 6 over an 8 — so the T tells Keyflow "this is the meter." (It's the meter's version of the # that marks a key.)

One bar, then back: !T

Often a meter only wobbles for a single bar — one bar of 2/4 in a stream of 4/4. Prefix the change with ! and it lasts exactly one measure, then snaps back to the prevailing meter on its own, with no closing T needed:

kf
VS
G  D/F#  Em  G   !T2/4 Am   G  D

Am is that one bar of 2/4; the G D after it are already back in 4/4. The ! is the same "just this once" mark you can put on a chord duration — here it scopes the meter change to a single measure instead of letting it stick.

What's next

  • Annotations & Expression — the markings that sit on top of the notes: staff text, instrument cues, dynamics, and hairpins.